0001558370-23-008846 | 10-Q | XBRL Viewer

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Document And Entity Information - shares	3 Months Ended
Document And Entity Information - shares	Mar. 31, 2023	May 04, 2023
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2023
Document Transition Report	false
Entity File Number	000-31311
Entity Registrant Name	PDF SOLUTIONS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	25-1701361
Entity Address, Address Line One	2858 De La Cruz Blvd.
Entity Address, City or Town	Santa Clara
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95050
City Area Code	408
Local Phone Number	280-7900
Title of 12(b) Security	Common Stock, $0.00015 par value
Trading Symbol	PDFS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		37,852,259
Entity Central Index Key	0001120914
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2023

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 114,382	$ 119,624
Short-term investments	19,146	19,557
Accounts receivable, net of allowance of $890 as of March 31, 2023 and December 31, 2022	47,048	42,164
Prepaid expenses and other current assets	12,565	12,063
Total current assets	193,141	193,408
Property and equipment, net	41,723	40,174
Operating lease right-of-use assets, net	5,712	6,002
Goodwill	14,123	14,123
Intangible assets, net	17,177	18,055
Deferred tax assets, net	90	64
Other non-current assets	7,322	6,845
Total assets	279,288	278,671
Current liabilities:
Accounts payable	6,289	6,388
Accrued compensation and related benefits	13,869	16,948
Accrued and other current liabilities	5,868	5,581
Operating lease liabilities - current portion	1,572	1,412
Deferred revenues - current portion	26,322	26,019
Billings in excess of recognized revenues	342	1,852
Total current liabilities	54,262	58,200
Long-term income taxes payable	2,637	2,622
Non-current operating lease liabilities	5,597	5,932
Other non-current liabilities	3,367	1,905
Total liabilities	65,863	68,659
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.00015 par value, 5,000 shares authorized, no shares issued and outstanding
Common stock, $0.00015 par value, 70,000 shares authorized; shares issued 49,150 and 48,613, respectively; shares outstanding 37,836 and 37,431, respectively	6	6
Additional paid-in-capital	454,307	447,415
Treasury stock at cost, 11,315 and 11,182 shares, respectively	(137,810)	(133,709)
Accumulated deficit	(100,795)	(101,150)
Accumulated other comprehensive loss	(2,283)	(2,550)
Total stockholders' equity	213,425	210,012
Total liabilities and stockholders' equity	$ 279,288	$ 278,671

CONDENSED CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
CONDENSED CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for credit losses	$ 890
Preferred stock, par value (in dollars per share)	$ 0.00015	$ 0.00015
Preferred stock, shares authorized (in shares)	5,000	5,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.00015	$ 0.00015
Common stock, shares authorized (in shares)	70,000	70,000
Common stock, shares issued (in shares)	49,150	48,613
Common stock, shares outstanding (in shares)	37,836	37,431
Treasury stock, shares (in shares)	11,315	11,182

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenues:
Revenues	$ 40,759	$ 33,498
Costs and Expenses:
Costs of revenues	11,904	11,529
Research and development	13,051	14,089
Selling, general and administrative	15,645	10,839
Amortization of acquired intangible assets	325	314
Interest and other expense (income), net	(911)	(310)
Income (loss) before income taxes	745	(2,963)
Income tax expense	390	1,187
Net income (loss)	355	(4,150)
Other comprehensive loss:
Foreign currency translation adjustments, net of tax	260	(397)
Change in unrealized gain (loss) related to available-for-sale debt securities, net of tax	7	(34)
Total other comprehensive (loss)	267	(431)
Comprehensive income (loss)	$ 622	$ (4,581)
Net income (loss) per share, basic (in dollars per share)	$ 0.01	$ (0.11)
Net income (loss) per share, diluted (in dollars per share)	$ 0.01	$ (0.11)
Weighted average common shares used to calculate net income (loss) per share, basic (in shares)	37,737	37,606
Weighted average common shares used to calculate net income (loss) per share, diluted (in shares)	38,859	37,606
Analytics
Revenues:
Revenues	$ 36,326	$ 30,426
Integrated Yield Ramp
Revenues:
Revenues	$ 4,433	$ 3,072

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock Outstanding	Additional Paid-in Capital	Treasury Stock	Accumulated Deficit	Accumulated Other Comprehensive Loss	Total
Balances (in shares) at Dec. 31, 2021	37,411		10,003
Balances at Dec. 31, 2021	$ 6	$ 423,069	$ (104,705)	$ (97,721)	$ (1,064)	$ 219,585
Issuance of common stock in connection with employee stock purchase plan (in shares)	95
Issuance of common stock in connection with employee stock purchase plan		1,502				1,502
Issuance of common stock in connection with exercise of options (in shares)	75
Issuance of common stock in connection with exercise of options		675				675
Vesting of restricted stock units (in shares)	232
Purchases of treasury stock in connection with tax withholdings on restricted stock grants (in shares)			113
Purchases of treasury stock in connection with tax withholdings on restricted stock grants			$ (3,389)			(3,389)
Repurchase of common stock			$ (5,778)			(5,778)
Repurchase of common stock (in shares)	(219)		219
Stock-based compensation expense		5,553				5,553
Comprehensive income (loss)				(4,150)	(431)	(4,581)
Balances (in shares) at Mar. 31, 2022	37,594		10,335
Balances at Mar. 31, 2022	$ 6	430,799	$ (113,872)	(101,871)	(1,495)	213,567
Balances (in shares) at Dec. 31, 2022	37,431		11,182
Balances at Dec. 31, 2022	$ 6	447,415	$ (133,709)	(101,150)	(2,550)	210,012
Issuance of common stock in connection with employee stock purchase plan (in shares)	98
Issuance of common stock in connection with employee stock purchase plan		1,663				$ 1,663
Issuance of common stock in connection with exercise of options (in shares)	21					21
Issuance of common stock in connection with exercise of options		345				$ 345
Vesting of restricted stock units (in shares)	286
Purchases of treasury stock in connection with tax withholdings on restricted stock grants (in shares)			133
Purchases of treasury stock in connection with tax withholdings on restricted stock grants			$ (4,101)			(4,101)
Stock-based compensation expense		4,884				4,884
Comprehensive income (loss)				355	267	622
Balances (in shares) at Mar. 31, 2023	37,836		11,315
Balances at Mar. 31, 2023	$ 6	$ 454,307	$ (137,810)	$ (100,795)	$ (2,283)	$ 213,425

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net income (loss)	$ 355	$ (4,150)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	1,304	1,380
Stock-based compensation expense	4,884	5,553
Amortization of acquired intangible assets	878	867
Amortization of costs capitalized to obtain revenue contracts	456	173
Deferred taxes	(23)	(11)
Other	(231)	37
Changes in operating assets and liabilities:
Accounts receivable	(4,872)	2,296
Prepaid expenses and other current assets	(973)	(976)
Operating lease right-of-use assets	302	918
Other non-current assets	(476)	278
Accounts payable	1,261	(2,069)
Accrued compensation and related benefits	(3,132)	(864)
Accrued and other liabilities	260	582
Deferred revenues	723	(225)
Billings in excess of recognized revenues	(1,510)	245
Operating lease liabilities	(188)	(1,038)
Net cash provided by (used in) operating activities	(982)	2,996
Cash flows from investing activities:
Proceeds from maturities and sales of short-term investments	7,000	35,000
Purchases of short-term investments	(6,351)	(20,959)
Purchases of property and equipment	(2,902)	(1,765)
Net cash provided by (used in) investing activities	(2,253)	12,276
Cash flows from financing activities:
Proceeds from exercise of stock options	345	675
Proceeds from employee stock purchase plan	1,663	1,502
Payments for taxes related to net share settlement of equity awards	(4,101)	(3,389)
Repurchases of common stock		(5,778)
Net cash used in financing activities	(2,093)	(6,990)
Effect of exchange rate changes on cash and cash equivalents	86	(167)
Net change in cash and cash equivalents	(5,242)	8,115
Cash and cash equivalents at beginning of period	119,624	27,684
Cash and cash equivalents at end of period	114,382	35,799
Reconciliation of cash and cash equivalents to the balance sheets:
Cash and cash equivalents	114,382
Total cash and cash equivalents	114,382	35,799
Supplemental disclosure of cash flow information:
Cash paid during the period for taxes	1,985	1,254
Cash paid for amounts included in the measurement of operating lease liabilities	276	430
Supplemental disclosure of noncash information:
Property and equipment received and accrued in accounts payable and accrued and other liabilities	1,714	1,923
Advances for purchase of fixed assets transferred from prepaid assets to property and equipment	$ 21	$ 120

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

3 Months Ended

Mar. 31, 2023

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

1. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The interim unaudited condensed consolidated financial statements included herein have been prepared by PDF Solutions, Inc. (the “Company”) pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”), including the instructions to the Quarterly Report on Form 10-Q and Article 10 of Regulation S-X. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted. The interim unaudited condensed consolidated financial statements reflect, in the opinion of management, all adjustments necessary (consisting only of normal recurring adjustments) to present a fair statement of results for the interim periods presented. The operating results for any interim period are not necessarily indicative of the results that may be expected for other interim periods or the full fiscal year. The accompanying interim unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on March 1, 2023.

The interim unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries after the elimination of all intercompany balances and transactions.

The accompanying interim unaudited condensed consolidated balance sheet as of December 31, 2022, has been derived from the audited consolidated financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates in these financial statements include revenue recognition, the estimated useful lives of property and equipment and intangible assets, assumptions made in analysis of allowance for credit losses, impairment of goodwill and long-lived assets, valuation for deferred tax assets, and accounting for lease obligations, stock-based compensation expense, and income tax uncertainties and contingencies. Actual results could differ from those estimates and may result in material effects on the Company’s operating results and financial position.

Recent Accounting Standards

Accounting Standards Adopted

In June 2016, the Financial Accounting Standards Board (“FASB’) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU No. 2016-13”), which requires measurement and recognition of expected credit losses for financial assets held at the reporting date based on internal information, external information, or a combination of both relating to past events, current conditions, and reasonable and supportable forecasts. ASU No. 2016-13 replaces the existing incurred loss impairment model with a forward-looking expected credit loss model, which will result in earlier recognition of credit losses. Subsequent to the issuance of ASU No. 2016-13, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments – Credit Losses, ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments – Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instrument, ASU No. 2019-05, Financial Instruments – Credit Losses (Topic 326) Targeted Transition Relief, ASU No. 2016-13, ASU No. 2019-10 Financial Instruments-Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842), and ASU No. 2019-11 Codification Improvements to Topic 326, Financial Instruments-Credit Losses. The subsequent ASUs do not change the core principle of the guidance in

ASU No. 2016-13. Instead, these amendments are intended to clarify and improve operability of certain topics included within ASU No. 2016-13.

The Company adopted this standard on January 1, 2023, using a modified retrospective approach, which requires a cumulative-effect adjustment to retained earnings as of the beginning of the period of adoption with prior periods not restated. The adoption of ASU No. 2016-13 did not have a material impact on the Company’s condensed consolidated financial statements.

Accounting Standards Not Yet Adopted

Management has reviewed other recently issued accounting pronouncements issued or proposed by the FASB, and does not believe any of these accounting pronouncements has had or will have a material impact on the condensed consolidated financial statements.

REVENUE FROM CONTRACT WITH CUSTOMERS

3 Months Ended

Mar. 31, 2023

REVENUE FROM CONTRACT WITH CUSTOMERS

REVENUE FROM CONTRACT WITH CUSTOMERS

2. REVENUE FROM CONTRACTS WITH CUSTOMERS

The Company derives revenue from two sources: Analytics revenue and Integrated Yield Ramp revenue.

The Company recognizes revenue in accordance with FASB Accounting Standards Codification Topic 606, Revenue from Contracts with Customers, and its related amendments (collectively known as “ASC 606”). ASC 606 outlines a single comprehensive model to use in accounting for revenue arising from contracts with customers. Revenue is recognized when control of products or services is transferred to customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those promised products or services.

The Company determines revenue recognition through the following five steps:

●

Identification of the contract, or contracts, with a customer

●

Identification of the performance obligations in the contract

●

Determination of the transaction price

●

Allocation of the transaction price to the performance obligations in the contract

●

Recognition of revenue when, or as, performance obligations are satisfied

The Company accounts for a contract when it has approval and commitment from both parties, the rights of the parties are identified, payment terms are identified, the contract has commercial substance, and collectibility of consideration is probable.

Contracts with multiple performance obligations

The Company enters into contracts that can include various combinations of licenses, products and services, some of which are distinct and are accounted for as separate performance obligations. For contracts with multiple performance obligations, the Company allocates the transaction price of the contract to each performance obligation on a relative basis using the standalone selling price (“SSP”).

Analytics Revenue

Analytics revenue is derived from the following primary offerings: licenses and services for standalone software (which is primarily Exensio^® and Cimetrix^® products), software-as-a-service (“SaaS”) (which is primarily Exensio^® products), and Design-for-Inspection™ (“DFI™”) systems and Characterization Vehicle^® (“CV^®) systems that do not include performance incentives based on customers’ yield achievement.

Revenue from standalone software is recognized depending on whether the license is perpetual or time-based. Perpetual (one-time charge) license software is recognized at the time of the inception of the arrangement when control transfers to the customers if the software license is considered as a separate performance obligation from the services offered by the Company.

Revenue from post-contract support is recognized over the contract term on a straight-line basis, because the Company is providing (i) support and (ii) unspecified software updates on a when-and-if available basis over the contract term. Revenue from time-based-licensed software is allocated to each performance obligation and is recognized either at a point in time or over time as follows. The license component is recognized at the time when control transfers to customers, with the post-contract support component recognized ratably over the committed term of the contract. For contracts with any combination of licenses, support, and other services, distinct performance obligations are accounted for separately. For contracts with multiple performance obligations, the Company allocates the transaction price of the contract to each performance obligation on a relative basis using the SSP attributed to each performance obligation.

Revenue from SaaS arrangements, which allow for the use of a cloud-based software product or service over a contractually determined period of time without the customer having to take possession of software, is accounted for as a subscription and is recognized as revenue ratably, on a straight-line basis, over the subscription period beginning on the date the service is first made available to customers. For contracts with any combination of SaaS and related services, distinct performance obligations are accounted for separately. For contracts with multiple performance obligations, the Company allocates the transaction price of the contract to each performance obligation on a relative basis using the SSP attributed to each performance obligation.

Revenue from DFI systems and CV systems (including Characterization services) that do not include performance incentives based on customers’ yield achievement is recognized primarily as services are performed. Where there are distinct performance obligations, the Company allocates revenue to all deliverables based on their SSPs. For those contracts with multiple performance obligations, the Company allocates the transaction price of the contract to each performance obligation on a relative basis using the SSP attributed to each performance obligation. Where there are not discrete performance obligations, historically, revenue is primarily recognized as services are performed using a percentage of completion method based on costs or labor-hours inputs, whichever is the most appropriate measure of the progress towards completion of the contract. The estimation of percentage of completion method is complex and subject to many variables that require significant judgment. Please refer to the “Significant Judgments” section of this Note for further discussion.

Integrated Yield Ramp Revenue

Integrated Yield Ramp revenue is derived from the Company’s fixed-fee engagements that include performance incentives based on customers’ yield achievement (which consists primarily of Gainshare royalties) typically based on customer’s wafer shipments, pertaining to these fixed-price contracts, which royalties are variable.

Revenue under these project-based contracts, which are delivered over a specific period of time, typically for a fixed fee component paid on a set schedule, is recognized as services are performed using a percentage of completion method based on costs or labor-hours inputs, whichever is the most appropriate measure of the progress towards completion of the contract. Where there are distinct performance obligations, the Company allocates revenue to all deliverables based on their SSPs and allocates the transaction price of the contract to each performance obligation on a relative basis using SSP. Similar to the services provided in connection with DFI systems and CV systems that are contributing to Analytics revenue, due to the nature of the work performed in these arrangements, the estimation of percentage of completion method is complex and subject to many variables that require significant judgment. Please refer to the “Significant Judgments” section of this Note for further discussion.

The Gainshare contained in Integrated Yield Ramp contracts is a variable fee related to continued usage of the Company’s intellectual property after the fixed-fee service period ends, based on a customer’s yield achievement. Revenue derived from Gainshare is contingent upon the Company’s customers reaching certain defined production yield levels. Gainshare periods are generally subsequent to the delivery of all contractual services and performance obligations. The Company records Gainshare as a usage-based royalty derived from customers’ usage of intellectual property and records it in the same period in which the usage occurs.

Disaggregation of Revenue

The Company disaggregates revenue from contracts with customers into the timing of the transfer of goods and services and the geographical regions. The Company determined that disaggregating revenue into these categories achieves the disclosure objective to depict how the nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factors.

The Company’s performance obligations are satisfied either over time or at a point-in-time. The following table represents a disaggregation of revenue percentage by timing of revenue:


	Three Months Ended March 31,
	2023		2022
Over time	80	%	70	%
Point-in-time	20	%	30	%
Total	100	%	100	%

International revenues accounted for approximately 43% and 48% of the Company’s total revenues during the three months ended March 31, 2023 and 2022, respectively. See Note 10, Customer and Geographic Information.

Significant Judgments

Judgments and estimates are required under ASC 606. Due to the complexity of certain contracts, the actual revenue recognition treatment required under ASC 606 for the Company’s arrangements may be dependent on contract-specific terms and may vary in some instances.

For revenue under project-based contracts for fixed-price implementation services, revenue is recognized as services are performed using a percentage-of-completion method based on costs or labor-hours input method, whichever is the most appropriate measure of the progress towards completion of the contract. Due to the nature of the work performed in these arrangements, the estimation of percentage of completion method is complex, subject to many variables and requires significant judgment. Key factors reviewed by the Company to estimate costs to complete each contract are future labor and product costs and expected productivity efficiencies. If circumstances arise that change the original estimates of revenues, costs, or extent of progress toward completion, revisions to the estimates are made. These revisions may result in increases or decreases in estimated revenues or costs, and such revisions are reflected in revenue on a cumulative catch-up basis in the period in which the circumstances that gave rise to the revision become known.

The Company’s contracts with customers often include promises to transfer products, software licenses and provide services, including professional services, technical support services, and rights to unspecified updates to a customer. Determining whether licenses and services are distinct performance obligations that should be accounted for separately, or not distinct and thus accounted for together, requires significant judgment. The Company rarely licenses software on a standalone basis, so the Company is required to estimate the range of SSPs for each performance obligation. In instances where SSP is not directly observable because the Company does not license the software or sell the service separately, the Company determines the SSP using information that may include market conditions and other observable inputs.

The Company is required to record Gainshare revenue in the same period in which the usage occurs. Because the Company generally does not receive the acknowledgment reports from its customers during a given quarter within the time frame necessary to adequately review the reports and include the actual amounts in quarterly results for such quarter, the Company accrues the related revenue based on estimates of customers underlying sales achievement. The Company’s estimation process can be based on historical data, trends, seasonality, changes in the contract rate, knowledge of the changes in the industry and changes in the customer’s manufacturing environment learned through discussions with customers and sales personnel. As a result of accruing revenue for the quarter based on such estimates, adjustments will be required in the following quarter to true-up revenue to the actual amounts reported.

Contract Balances

The Company performs its obligations under a contract with a customer by licensing software or providing services in exchange for consideration from the customer. The timing of the Company’s performance often differs from the timing of the customer’s payment, which results in the recognition of a receivable, a contract asset or a contract liability.

The Company classifies the right to consideration in exchange for software or services transferred to a customer as either a receivable or a contract asset. A receivable is a right to consideration that is unconditional, as compared to a contract asset, which is a right to consideration that is conditional upon factors other than the passage of time. The majority of the Company’s contract assets represent unbilled amounts related to fixed-price service contracts when the revenue recognized exceeds the amount billed to the customer. The contract assets are generally classified as current and are recorded on a net basis with deferred revenue (i.e., contract liabilities) at the contract level. As of March 31, 2023 and December 31, 2022, the total contract assets included in prepaid expenses and other current assets in the accompanying condensed consolidated balance sheets were $2.9 million and $3.3 million, respectively. The Company did not record any asset impairment charges related to contract assets for the periods presented.

Deferred revenues and billings in excess of recognized revenues consist substantially of amounts invoiced in advance of revenue recognition and are recognized as the revenue recognition criteria are met. Deferred revenues that will be recognized during the succeeding twelve-month period are recorded as current deferred revenues and the remaining portion is recorded in other non-current liabilities in the accompanying condensed consolidated balance sheets. As of March 31, 2023, and December 31, 2022, the non-current portion of deferred revenues included in non-current liabilities was $2.3 million and $1.9 million, respectively. Revenue recognized that was included in the deferred revenues and billings in excess of recognized revenues balances at the beginning of each reporting period was $11.4 million and $6.9 million during the three months ended March 31, 2023 and 2022, respectively.

As of March 31, 2023, the aggregate amount of the transaction price allocated to the remaining performance obligations related to customer contracts that were unsatisfied or partially unsatisfied was approximately $261.2 million. Given the applicable contract terms with customers, more than half of this amount is expected to be recognized as revenue over the next two years with the remainder to be recognized thereafter. This amount does not include insignificant contracts to which the customer is not committed, nor significant contracts for which the Company recognizes revenue equal to the amount the Company has the right to invoice for services performed, or future sales-based or usage-based royalty payments in exchange for a license of intellectual property. This amount is subject to change due to future revaluations of variable consideration, terminations, other contract modifications, or currency adjustments. The estimated timing of the recognition of remaining unsatisfied performance obligations is subject to change and is affected by changes to the scope, change in timing of delivery of products and services, or contract modifications.

The adjustment to revenue recognized from performance obligations satisfied (or partially satisfied) in previous periods was an increase of $2.5 million and an increase of $0.2 million during the three months ended March 31, 2023, and 2022, respectively. These amounts primarily represent changes in estimated percentage-of-completion based contracts and changes in actual versus estimated Gainshare.

Costs to obtain or fulfill a contract

The Company capitalizes the incremental costs to obtain or fulfill a contract with a customer, including direct sales commissions and related fees, when it expects to recover those costs. Amortization expense related to these capitalized costs is recognized over the period associated with the revenue from which the cost was incurred. Total capitalized direct sales commission costs included in prepaid expenses and other current assets in the accompanying condensed consolidated balance sheets as of March 31, 2023, and December 31, 2022, were $1.8 million and $1.7 million, respectively. Total capitalized direct sales commission costs included in other non-current assets in the accompanying condensed consolidated balance sheets as of March 31, 2023, and December 31, 2022, were $3.2 million and $2.1 million, respectively. Amortization of these assets was $0.5 million and $0.2 million during the three months ended March 31, 2023 and 2022, respectively. There was no impairment loss in relation to the costs capitalized for the periods presented.

Practical expedient

The Company does not adjust the transaction price for the effects of a significant financing component when the period between the transfers of the promised good or service to the customer and payment for that good or service by the customer is expected to be one year or less. The Company assessed each of its revenue generating arrangements in order to determine whether a significant financing component exists, and determined its contracts did not include a significant financing component during the three months ended March 31, 2023 and 2022.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI https://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

STRATEGIC PARTNERSHIP AGREEMENT WITH ADVANTEST AND RELATED PARTY TRANSACTIONS

3 Months Ended

Mar. 31, 2023

STRATEGIC PARTNERSHIP AGREEMENT WITH ADVANTEST AND RELATED PARTY TRANSACTIONS

STRATEGIC PARTNERSHIP AGREEMENT WITH ADVANTEST AND RELATED PARTY TRANSACTIONS

3. STRATEGIC PARTNERSHIP AGREEMENT WITH ADVANTEST AND RELATED PARTY TRANSACTIONS

On July 29, 2020, the Company entered into a long-term strategic partnership with Advantest Corporation through its wholly-owned subsidiary, Advantest America, Inc. (collectively referred to herein as “Advantest”) that included the following agreements, which were all negotiated on arm’s length basis with commercial customary terms.

●

A Securities Purchase Agreement for the purchase by Advantest of an aggregate of 3,306,924 shares of the Company’s common stock for aggregate gross proceeds of $65.2 million and a related Stockholder Agreement.

●

An Amendment #1 to that certain Software License and Related Services Agreement, dated as of March 25, 2020, for an exclusive commercial arrangement in which the Company and Advantest collaborate on, and the Company initially hosts, develops and maintains, an Advantest-specific cloud layer on the Exensio platform. On June 5, 2022, the parties amended Amendment #1 to provide another approved Data Exchange Network (DEX) Site (as defined therein). On November 11, 2022, the parties entered into a further amendment to Amendment #1 that provided, effective October 31, 2022: (i) flexibility for Advantest to spend the remainder of their committed $50.0 million over the remainder of the original term on its choice of products and services from a price list, instead of limiting Advantest to the original, fixed bundle of software and services; (ii) revised exclusivity; and (iii) the Company with free access/use of certain Advantest software.

●

An Amended and Restated Master Development Agreement with Advantest, pursuant to which the Company and Advantest agreed to collaborate on extensions to or combinations of both of their existing technology and new technology to address mutual customers’ needs through one or more development phases subject to certain conditions as set forth therein. Costs and expenses incurred related to this agreement were not significant for the three months ended March 31, 2023 and 2022.

●

A Master Commercial Terms and Support Services Agreement for the commercialization and support of integrated products of the Company and Advantest that are the outcome of the above development agreement. No material costs and expenses were incurred related to the Commercial Agreement with Advantest during the three months ended March 31, 2023 and 2022.

Analytics revenue recognized from Advantest was $1.8 million and $2.6 million during the three months ended March 31, 2023 and 2022, respectively. There were no outstanding accounts receivable from Advantest as of March 31, 2023. Accounts receivable from Advantest amounted to $0.3 million as of December 31, 2022. Deferred revenue amounted to $5.9 million and $7.1 million as of March 31, 2023, and December 31, 2022, respectively. There was no occurrence of any termination events under these agreements as of the issuance of these condensed consolidated financial statements.

BALANCE SHEET COMPONENTS

3 Months Ended

Mar. 31, 2023

BALANCE SHEET COMPONENTS

BALANCE SHEET COMPONENTS

4. BALANCE SHEET COMPONENTS

Accounts receivable

Accounts receivable include amounts that are unbilled at the end of the period that are expected to be billed and collected within a 12-month period. Unbilled accounts receivable, included in accounts receivable, totaled $16.1 million and $13.5 million as of March 31, 2023, and December 31, 2022, respectively. Unbilled accounts receivable that are not expected to be billed and collected during the succeeding 12-month period is recorded in other non-current assets and totaled $0.7 million and $0.8 million as of March 31, 2023, and December 31, 2022, respectively.

The Company performs ongoing credit evaluations of its customers’ financial condition. An allowance for credit losses is maintained for probable credit losses based upon the Company’s assessment of the expected collectability of the accounts receivable. The allowance for credit losses is reviewed on a quarterly basis to assess the adequacy of the allowance.

Property and equipment

Property and equipment, net consist of the following (in thousands):


	March 31,		December 31,
	2023		2022
Computer equipment	$	11,930	$	11,853
Software		5,407		5,395
Furniture, fixtures, and equipment		2,488		2,484
Leasehold improvements		6,469		6,467
Laboratory and other equipment		4,494		4,431
Test equipment		28,403		28,403
Property and equipment in progress:
DFI™ system assets		23,596		22,231
CV® system and other assets		6,447		5,105
		89,234		86,369
Less: Accumulated depreciation and amortization		(47,511)		(46,195)
Total	$	41,723	$	40,174

Test equipment mainly includes DFI™ system and CV^® system assets at customer sites that are contributing to revenue. Property and equipment in progress represent the development or construction of property and equipment that have not yet been placed in service for the Company’s intended use and are not depreciated.

Depreciation and amortization expense was $1.3 million and $1.4 million during the three months ended March 31, 2023 and 2022, respectively.

Goodwill and Intangible Assets, Net

As of March 31, 2023, and December 31, 2022, the carrying amount of goodwill was $14.1 million.

Intangible assets, net, consisted of the following (in thousands):


		March 31, 2023						December 31, 2022
	Amortization	Gross				Net		Gross				Net
	Period	Carrying		Accumulated		Carrying		Carrying		Accumulated		Carrying
	(Years)	Amount		Amortization		Amount		Amount		Amortization		Amount
Acquired identifiable intangibles:
Customer relationships	1-10	$	9,407	$	(6,845)	$	2,562	$	9,407	$	(6,684)	$	2,723
Developed technology	4-9		33,635		(20,244)		13,391		33,635		(19,647)		13,988
Tradename and trademarks	2-10		1,598		(945)		653		1,598		(918)		680
Patent	6-10		2,100		(1,717)		383		2,100		(1,696)		404
Noncompetition agreements	3		848		(660)		188		848		(588)		260
Total		$	47,588	$	(30,411)	$	17,177	$	47,588	$	(29,533)	$	18,055

The weighted average amortization period for acquired identifiable intangible assets was 5.7 years as of March 31, 2023. The following table summarizes intangible assets amortization expense in the accompanying condensed consolidated statements of comprehensive income (loss) (in thousands):


	Three Months Ended March 31,
	2023		2022
Amortization of acquired technology included under Costs of Revenues	$	553	$	553
Amortization of acquired intangible assets presented separately under Costs and Expenses		325		314
Total amortization of acquired intangible assets	$	878	$	867

The Company expects annual amortization of acquired identifiable intangible assets to be as follows (in thousands):


Year Ending December 31,	Amount
2023 (remaining nine months)	$	2,613
2024		3,093
2025		2,928
2026		2,759
2027		2,606
2028 and thereafter		3,178
Total future amortization expense	$	17,177

There were no impairment charges for goodwill and intangible assets during the three months ended March 31, 2023 and 2022.

LEASES

3 Months Ended

Mar. 31, 2023

LEASES

LEASES

5. LEASES

The Company leases administrative and sales offices and certain equipment under non-cancellable operating leases, which contain various renewal options and, in some cases, require payment of common area costs, taxes and utilities. These operating leases expire at various dates through 2028. The Company had no leases that were classified as a financing lease as of March 31, 2023, and December 31, 2022.

In the first quarter of 2022, the Company early terminated an office lease contract. The termination of this lease reduced the Company’s operating lease right-of-use assets and lease liabilities by approximately $0.5 million and $0.6 million, respectively. The gain from the lease termination of approximately $0.1 million was recorded under selling, general, and administrative expense in the accompanying condensed consolidated statement of comprehensive income (loss) for the three months ended March 31, 2022.

Lease expense was comprised of the following (in thousands):


	Three Months Ended March 31,
	2023		2022
Operating lease expense (1)	$	387	$	345
Short-term lease and variable lease expense (2)		228		283
Total lease expense	$	615	$	628

(1)

Net of gain recognized upon lease termination of $0.1 million in the three months ended March 31, 2022.

(2)

Leases with an initial term of 12 months or less are not recorded on the accompanying condensed consolidated balance sheets, and the Company recognizes lease expense for these leases on a straight-line basis over the lease term. Variable lease expense for the periods presented primarily included common area maintenance charges.

Supplemental condensed consolidated balance sheets information related to operating leases was as follows:


	March 31,			December 31,
	2023			2022
Weighted average remaining lease term under operating leases (in years)		5.1			5.3
Weighted average discount rate for operating lease liabilities		4.87	%		4.87	%

Maturities of operating lease liabilities as of March 31, 2023, were as follows (in thousands):


Year Ending December 31,	Amount (1)
2023 (remaining nine months)	$	1,299
2024		1,638
2025		1,551
2026		1,357
2027		1,294
2028 and thereafter		991
Total future minimum lease payments	$	8,130
Less: Interest (2)		(961)
Present value of future minimum lease payments under operating lease liabilities (3)	$	7,169

(1)

As of March 31, 2023, the total operating lease liability includes approximately $0.9 million related to an option to extend a lease term that is reasonably certain to be exercised.

(2)

Calculated using incremental borrowing interest rate for each lease.

(3)

Includes the current portion of operating lease liabilities of $1.6 million as of March 31, 2023.

STOCKHOLDERS' EQUITY

3 Months Ended

Mar. 31, 2023

STOCKHOLDERS EQUITY

STOCKHOLDERS' EQUITY

6. STOCKHOLDERS’ EQUITY

Stock Repurchase Program

On June 4, 2020, the Company’s Board of Directors adopted a stock repurchase program (the “2020 Program”) to repurchase up to $25.0 million of the Company’s common stock both on the open market and in privately negotiated transactions, including through Rule 10b5-1 plans, over the next two years. During the three months ended March 31, 2022, 218,858 shares were repurchased by the Company under the 2020 Program at an average price of $26.40 per share for an aggregate total price of $5.8 million. In total, 470,070 shares were repurchased under the 2020 Program at an average price of $21.91 per share, for an aggregate total price of $10.3 million.

On April 11, 2022, the Board of Directors terminated the 2020 Program, and adopted a new program (the “2022 Program”) to repurchase up to $35.0 million of the Company’s common stock both on the open market and in privately negotiated transactions, from time to time, over the next two years. In total, the Company has repurchased 714,600 shares under the 2022 Program at an average price of $23.36 per share for an aggregate total price of $16.7 million.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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+ Details

EMPLOYEE BENEFIT PLANS

3 Months Ended

Mar. 31, 2023

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS

7. EMPLOYEE BENEFIT PLANS

On March 31, 2023, the Company had the following stock-based compensation plans:

Employee Stock Purchase Plan

In July 2001, the Company’s stockholders initially approved the 2001 Employee Stock Purchase Plan, which was subsequently amended and restated in 2010 (as amended, the “2010 Purchase Plan”) to extend the term of the plan through May 17, 2020. Under the 2010 Purchase Plan, eligible employees could contribute up to 10% of their compensation, as defined in the 2010 Purchase Plan, towards the purchase of shares of PDF common stock at a price of 85% of the lower of the fair market value at the beginning of the offering period or the end of the purchase period. The 2010 Purchase Plan provided for twenty-four-month offering periods with four six-month purchase periods in each offering period. The 2010 Purchase Plan

expired on May 17, 2020. Existing offering periods under the 2010 Plan continued through the applicable expiration date and the final offering period expired on January 31, 2022. On June 15, 2021, the Company’s stockholders approved the 2021 Employee Stock Purchase Plan, which has a ten-year term (the “2021 Purchase Plan” and, together with the 2010 Purchase Plan, the “Employee Purchase Plans”). The terms of the 2021 Purchase Plan are substantially similar to those of the 2010 Purchase Plan. A twenty-four-month offering period under the 2021 Purchase Plan commenced on August 1, 2021.

The Company estimated the fair value of purchase rights granted under the 2021 Purchase Plan during the period using the Black-Scholes-Merton option-pricing model with the following weighted average assumptions, resulting in the following weighted average fair values:


	Three Months Ended March 31,
	2023			2022
Expected life (in years)		1.25			1.25
Volatility		46.70	%		48.90	%
Risk-free interest rate		4.48	%		0.86	%
Expected dividend		—			—
Weighted average fair value of purchase rights granted during the period	$	11.90		$	10.76

During the three months ended March 31, 2023, a total of 98,216 shares were issued under the 2021 Purchase Plan, at a weighted average purchase price of $16.93 per share. During the three months ended March 31, 2022, a total of 90,040 shares were issued under the 2021 Purchase Plan, at a weighted average purchase price of $15.90 per share. During the three months ended March 31, 2022, a total of 5,203 shares were issued under the 2010 Purchase Plan, at a weighted average purchase price of $13.40 per share. As of March 31, 2023, unrecognized compensation cost related to the 2021 Purchase Plan was $1.0 million. This estimated unrecognized cost is expected to be recognized over a weighted average period of 1.1 years.

As of March 31, 2023, 719,701 shares were available for future issuance under the 2021 Purchase Plan.

Stock Incentive Plans

On November 16, 2011, the Company’s stockholders initially approved the 2011 Stock Incentive Plan, which has been amended and restated and approved by the Company’s stockholders a number of times since then (as approved by the stockholders through the date of this report, the “2011 Plan”) and currently expires in 2030. Under the 2011 Plan, the Company may award stock options, stock appreciation rights (“SARs”), stock grants or stock units covering shares of the Company’s common stock to employees, directors, non-employee directors and contractors. The aggregate number of shares reserved for awards under the 2011 Plan is 12.8 million shares, plus up to 3.5 million shares previously issued under the 2001 Stock Plan adopted by the Company in 2001, which expired in 2011 (the “2001 Plan”) that are either (i) forfeited or (ii) repurchased by the Company or are shares subject to awards previously issued under the 2001 Plan that expire or that terminate without having been exercised or settled in full on or after November 16, 2011. In case of awards other than options or SARs, the aggregate number of shares reserved under the 2011 Plan will be decreased at a rate of 1.33 shares issued pursuant to such awards. The exercise price for stock options must generally be at prices no less than the fair market value at the date of grant. Stock options generally expire ten years from the date of grant and become vested and exercisable over a four-year period.

On April 24, 2023, the Company’s Board of Directors approved another amendment and restatement of the 2011 Plan, which is subject to stockholder approval at the 2023 annual meeting of stockholders, to, among other things, increase the number of shares reserved for awards under it to a total of 13.8 million shares, which is an increase of an additional 1.0 million shares, and to extend the expiration to 2031.

As of March 31, 2023, 13.3 million shares of common stock were reserved to cover stock-based awards under the 2011 Plan, of which 3.6 million shares were available for future grant. The number of shares reserved and available under the 2011 Plan includes 0.5 million shares that were subject to awards previously made under the 2001 Plan and were forfeited, expired or repurchased by the Company after the adoption of the 2011 Plan through March 31, 2023. As of March 31, 2023, there were no outstanding awards that had been granted outside of the 2011 or 2001 Plans (collectively, the “Stock Plans”).

The Company estimated the fair value of share-based awards granted under the 2011 Stock Plan during the period using the Black-Scholes-Merton option-pricing model. There were no stock options granted during the three months ended March 31, 2023 and 2022.

Stock-Based Compensation

Stock-based compensation is estimated at the grant date based on the award’s fair value and is recognized on a straight-line basis over the vesting periods, generally four years. Stock-based compensation expense before taxes related to the Company’s stock plans and employee stock purchase plans was allocated as follows (in thousands):


	Three Months Ended March 31,
	2023		2022
Costs of revenues	$	964	$	728
Research and development		1,794		3,168
Selling, general, and administrative		2,126		1,657
Stock-based compensation expenses	$	4,884	$	5,553

Additional information with respect to options under the Stock Plans during the three months ended March 31, 2023, is as follows:


	Outstanding Options
				Weighted
		Weighted		Average
		Average		Remaining	Aggregate
	Number of	Exercise		Contractual	Intrinsic
	Options	Price		Term	Value
	(in thousands)	per Share		(Years)	(in thousands)
Outstanding, December 31, 2022	68	$	16.11
Granted	—		—
Exercised	(21)		16.42
Canceled	—		—
Expired	—		—
Outstanding, March 31, 2023	47	$	15.98	4.58	$	1,248
Vested and expected to vest, March 31, 2023	47	$	15.97	4.56	$	1,242
Exercisable, March 31, 2023	39	$	15.81	4.11	$	1,038

The aggregate intrinsic value in the table above represents the total intrinsic value based on the Company’s closing stock price of $42.40 per share as of March 31, 2023. The total intrinsic value of options exercised was $0.4 million during the three months ended March 31, 2023.

Total remaining unrecognized compensation cost related to unvested stock options as of March 31, 2023, which is expected to be fully recognized in 2023, and total fair value of shares vested during the three months ended March 31, 2023 were immaterial.

Nonvested restricted stock unit activity during the three months ended March 31, 2023, was as follows:


		Weighted
		Average Grant
	Shares	Date Fair Value
	(in thousands)	Per Share
Nonvested, December 31, 2022	2,124	$	21.29
Granted	46	$	33.46
Vested	(419)	$	20.62
Forfeited	(3)	$	19.69
Nonvested, March 31, 2023	1,748	$	21.78

As of March 31, 2023, there was $30.2 million of total unrecognized compensation cost related to restricted stock units. That cost is expected to be recognized over a weighted average period of 2.5 years. Restricted stock units do not have rights to dividends prior to vesting.

INCOME TAXES

3 Months Ended

Mar. 31, 2023

INCOME TAXES

INCOME TAXES

8. INCOME TAXES

Income tax expense decreased by $0.8 million for the three months ended March 31, 2023, to a $0.4 million income tax expense as compared to $1.2 million for the three months ended March 31, 2022. The Company’s effective tax rate expense was 52% and (40.0%) for the three months ended March 31, 2023 and 2022, respectively. The Company’s effective tax rate increased in the three months ended March 31, 2023, as compared to the same period in 2022, primarily due to increases in foreign taxes and changes in the year-to-date recognition of worldwide income.

The Company’s total amount of unrecognized tax benefits, excluding interest and penalties, as of March 31, 2023, was $15.2 million, of which $2.0 million, if recognized, would affect the Company’s effective tax rate. The Company’s total amount of unrecognized tax benefits, excluding interest and penalties, as of December 31, 2022, was $15.1 million, of which $2.0 million, if recognized, would affect the Company’s effective tax rate. As of March 31, 2023, the Company has recorded unrecognized tax benefits of $2.6 million, including interest and penalties of $0.7 million, as long-term taxes payable in the accompanying condensed consolidated balance sheet. The remaining $13.2 million has been recorded within the Company’s deferred tax assets (“DTAs”), which is subject to a full valuation allowance.

The valuation allowance was approximately $59.2 million as of March 31, 2023, and December 31, 2022, which was related to U.S. net federal and state DTAs. The worldwide net deferred tax assets balance as of March 31, 2023, and December 31, 2022, were not significant.

The Company conducts business globally and, as a result, files numerous consolidated and separate income tax returns in the U.S. federal and various state and foreign jurisdictions. For U.S. federal and California income tax purposes, the statute of limitations currently remains open for the tax years ended 2019 to present and 2018 to present, respectively. In addition, due to net operating loss carryback claims, the tax years 2013 through 2015 may be subject to federal examination and all of the net operating loss and research and development credit carryforwards that may be utilized in future years may be subject to federal and state examination. The Company is not subject to income tax examinations in any other of its major foreign subsidiaries’ jurisdictions.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

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-Publisher FASB
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-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

NET LOSS PER SHARE

3 Months Ended

Mar. 31, 2023

NET LOSS PER SHARE

NET LOSS PER SHARE

9. NET INCOME (LOSS) PER SHARE

Basic net income (loss) per share is computed by dividing net income (loss) by weighted average number of common shares outstanding for the period (excluding outstanding stock options and shares subject to repurchase). Diluted net income (loss) per share is computed using the weighted average number of common shares outstanding for the period plus the potential effect of dilutive securities which are convertible into common shares (using the treasury stock method), except in cases in

which the effect would be anti-dilutive. The following is a reconciliation of the numerators and denominators used in computing basic and diluted net income (loss) per share (in thousands except per share amount):


	Three Months Ended March 31,
	2023		2022
Numerator:
Net income (loss)	$	355	$	(4,150)
Denominator:
Basic weighted average shares outstanding		37,737		37,606
Effect of dilutive stock options, unvested restricted stock units, and shares of common stock expected to be issued under Employee Purchase Plans		1,122		—
Diluted weighted average shares outstanding		38,859		37,606

Net income (loss) per share:
Basic	$	0.01	$	(0.11)
Diluted	$	0.01	$	(0.11)

For the three months ended March 31, 2022, because the Company was in a loss position, basic net loss per share is the same as diluted net loss per share as the inclusion of the potential common shares would have been anti-dilutive.

The following table sets forth potential shares of common stock that were not included in the diluted net income (loss) per share calculation above because to do so would be anti-dilutive for the periods indicated (in thousands):


	Three Months Ended March 31,
	2023	2022
Outstanding options	—	102
Non-vested restricted stock units	9	905
Employee Stock Purchase Plan	—	94
Total	9	1,101

CUSTOMER AND GEOGRAPHIC INFORMATION

3 Months Ended

Mar. 31, 2023

CUSTOMER AND GEOGRAPHIC INFORMATION

CUSTOMER AND GEOGRAPHIC INFORMATION

10. CUSTOMER AND GEOGRAPHIC INFORMATION

Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker, or group, in deciding how to allocate resources and in assessing performance.

The Company’s chief operating decision maker, the chief executive officer, reviews discrete financial information presented on a consolidated basis for purposes of regularly making operating decisions, allocation of resources, and assessing financial performance. Accordingly, the Company considers itself to be in one operating and reporting segment, specifically the provision of services for differentiated data and analytics solutions to the semiconductor and electronics industries.

Revenues from an individual customer that are approximately 10% or more of the Company’s consolidated total revenues are as follows:


	Three Months Ended March 31,
Customer	2023		2022
A	38	%	33	%

Gross accounts receivable balances (including amounts that are unbilled) from individual customers that are approximately 10% or more of the Company’s gross accounts receivable balance are as follows:


	March 31,		December 31,
Customer	2023		2022
A	42	%	29	%
B	10	%	12	%
C	*	%	12	%

* represents less than 10%

Revenues from customers by geographic area based on the location of the customers’ work sites are as follows (amounts in thousands):


	Three Months Ended March 31,
	2023				2022
			Percentage				Percentage
	Revenues		of Revenues		Revenues		of Revenues
United States	$	23,274	57	%	$	17,491	52	%
China		6,956	17			4,120	12
Rest of the world		10,529	26			11,887	36
Total revenue	$	40,759	100	%	$	33,498	100	%

Long-lived assets, net by geographic area are as follows (in thousands):


	March 31,		December 31,
	2023		2022
United States (1)	$	46,137	$	44,730
Rest of the world		1,298		1,446
Total long-lived assets, net	$	47,435	$	46,176

(1) Includes assets deployed at customer sites which could be outside the U.S.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 32
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/topic&trid=2134510

+ Details

FAIR VALUE MEASUREMENTS

3 Months Ended

Mar. 31, 2023

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS

11. FAIR VALUE MEASUREMENTS

Fair value is the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants as of the measurement date. The multiple assumptions used to value financial instruments are referred to as inputs, and a hierarchy for inputs used in measuring fair value is established, that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. Observable inputs reflect assumptions market participants would use in pricing an asset or liability based on market data obtained from independent sources while unobservable inputs reflect a reporting entity’s pricing based upon its

own market assumptions. These inputs are ranked according to a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels.


Level 1 -	Inputs are quoted prices in active markets for identical assets or liabilities.

Level 2 -	Inputs are quoted prices for similar assets or liabilities in an active market, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable and market-corroborated inputs which are derived principally from or corroborated by observable market data.

Level 3 -	Inputs are derived from valuation techniques in which one or more significant inputs or value drivers are unobservable.

The following table represents the Company’s assets measured at fair value on a recurring basis as of March 31, 2023, and December 31, 2022, and the basis for those measurements (in thousands):


	Fair Value Measurements Using
			Quoted
			Prices in
			Active		Significant
			Markets for		Other
			Identical		Observable		Significant
	March 31,		Assets		Inputs		Unobservable
Assets	2023		(Level 1)		(Level 2)		Inputs (Level 3)
Cash equivalents
Money market mutual funds	$	76,204	$	76,204	$	—	$	—
U.S. Government securities (1)		2,999		2,999		—		—
Short-term investments (available-for-sale debt securities)
U.S. Government securities (1)		19,146		19,146		—		—
Total	$	98,349	$	98,349	$	—	$	—


	Fair Value Measurements Using
			Quoted
			Prices in
			Active		Significant
			Markets for		Other		Significant
			Identical		Observable		Unobservable
	December 31,		Assets		Inputs		Inputs
Assets	2022		(Level 1)		(Level 2)		(Level 3)
Cash equivalents
Money market mutual funds	$	75,738	$	75,738	$	—	$	—
U.S. Government securities (1)		1,990		1,990		—		—
Short-term investments (available-for-sale debt securities)
U.S. Government securities (1)		19,557		19,557		—		—
Total	$	97,285	$	97,285	$	—	$	—

(1)

As of March 31, 2023, and December 31, 2022, the amortized cost of the Company’s investments in U.S Government securities approximated their fair value due to their short-term maturities, and there have been no events or changes in circumstances that would have had a significant effect on the fair value of these securities in the periods presented. For the three months ended March 31, 2023, there were no material realized or unrealized gains or losses, either individually or in the aggregate.

COMMITMENTS AND CONTINGENCIES

3 Months Ended

Mar. 31, 2023

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES

12. COMMITMENTS AND CONTINGENCIES

Strategic Partnership with Advantest — See Note 3, Strategic Partnership Agreement with Advantest And Related Party Transactions, for the discussion about the Company’s commitments under the strategic partnership with Advantest.

Operating Leases — Refer to Note 5, Leases, for the discussion about the Company’s lease commitments.

Indemnifications — The Company generally provides a warranty to its customers that its software will perform substantially in accordance with documented specifications typically for a period of 90 days following initial delivery of its products. The Company also indemnifies certain customers from third-party claims of intellectual property infringement relating to the use of its products. Historically, costs related to these guarantees have not been significant. The Company is unable to estimate the maximum potential impact of these guarantees on its future results of operations.

Purchase Obligations — The Company has purchase obligations with certain suppliers for the purchase of goods and services entered into in the ordinary course of business. As of March 31, 2023, total outstanding purchase obligations were $25.7 million, the majority of which is due within the next 24 months.

Indemnification of Officers and Directors — As permitted by the Delaware general corporation law, the Company has included a provision in its certificate of incorporation to eliminate the personal liability of its officers and directors for monetary damages for breach or alleged breach of their fiduciary duties as officers or directors, other than in cases of fraud or other willful misconduct.

In addition, the Bylaws of the Company provide that the Company is required to indemnify its officers and directors even when indemnification would otherwise be discretionary, and the Company is required to advance expenses to its officers and directors as incurred in connection with proceedings against them for which they may be indemnified. The Company has entered into indemnification agreements with its officers and directors containing provisions that are in some respects broader than the specific indemnification provisions contained in the Delaware general corporation law. The indemnification agreements require the Company to indemnify its officers and directors against liabilities that may arise by reason of their status or service as officers and directors other than for liabilities arising from willful misconduct of a culpable nature, to advance their expenses incurred as a result of any proceeding against them as to which they could be indemnified, and to obtain directors’ and officers’ insurance if available on reasonable terms. The Company has obtained directors’ and officers’ liability insurance in amounts comparable to other companies of the Company’s size and in the Company’s industry. Since a maximum obligation of the Company is not explicitly stated in the Company’s Bylaws or in its indemnification agreements and will depend on the facts and circumstances that arise out of any future claims, the overall maximum amount of the obligations cannot be reasonably estimated.

Legal Proceedings — From time to time, the Company is subject to various claims and legal proceedings that arise in the ordinary course of business. The Company accrues for losses related to litigation when a potential loss is probable, and the loss can be reasonably estimated in accordance with FASB requirements. As of March 31, 2023, the Company was not party to any material legal proceedings for which a loss was probable or an amount was accrued.

On May 6, 2020, the Company initiated an arbitration proceeding with the Hong Kong International Arbitration Center against SMIC New Technology Research & Development (Shanghai) Corporation (“SMIC”) due to SMIC’s failure to pay fees due to the Company under a series of contracts. The Company seeks to recover the unpaid fees, a declaration requiring SMIC to pay fees under the contracts in the future (or a lump sum payment to end the contract), and costs associated with bringing the arbitration proceeding. SMIC denies liability and an arbitration hearing was held in February 2023. A decision is expected within this calendar year, approximately.

SUBSEQUENT EVENTS

3 Months Ended

Mar. 31, 2023

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS

13. SUBSEQUENT EVENTS

Refer to Note 7, Employee Benefits Plans, for the discussion about the amendment to the 2011 Stock Incentive Plan.

SIGNIFICANT ACCOUNTING POLICIES (Policies)

3 Months Ended

Mar. 31, 2023

BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation, Policy

Basis of Presentation

Use of Estimates, Policy

Use of Estimates

Revenue from Contracts with Customers, Policy

The Company derives revenue from two sources: Analytics revenue and Integrated Yield Ramp revenue.

The Company determines revenue recognition through the following five steps:

●

Identification of the contract, or contracts, with a customer

●

Identification of the performance obligations in the contract

●

Determination of the transaction price

●

Allocation of the transaction price to the performance obligations in the contract

●

Recognition of revenue when, or as, performance obligations are satisfied

Contracts with multiple performance obligations

Analytics Revenue

Integrated Yield Ramp Revenue

Disaggregation of Revenue

The Company’s performance obligations are satisfied either over time or at a point-in-time. The following table represents a disaggregation of revenue percentage by timing of revenue:


	Three Months Ended March 31,
	2023		2022
Over time	80	%	70	%
Point-in-time	20	%	30	%
Total	100	%	100	%

Significant Judgments

Contract Balances

Costs to obtain or fulfill a contract

Practical expedient

Accounts Receivable, Policy

Accounts receivable

Stock-Based Compensation, Policy

Stock-Based Compensation

Fair Value Measurement, Policy

own market assumptions. These inputs are ranked according to a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels.


Level 1 -	Inputs are quoted prices in active markets for identical assets or liabilities.

Level 2 -	Inputs are quoted prices for similar assets or liabilities in an active market, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable and market-corroborated inputs which are derived principally from or corroborated by observable market data.

Level 3 -	Inputs are derived from valuation techniques in which one or more significant inputs or value drivers are unobservable.

Accounting Standards, Policy

Recent Accounting Standards

Accounting Standards Adopted

ASU No. 2016-13. Instead, these amendments are intended to clarify and improve operability of certain topics included within ASU No. 2016-13.

Accounting Standards Not Yet Adopted

- Definition

Disclosure of accounting policy for revenue from contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130561-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130563-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI https://asc.fasb.org/topic&trid=49130388

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 18
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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+ Details

- Definition

Disclosure of accounting policy for award under share-based payment arrangement. Includes, but is not limited to, methodology and assumption used in measuring cost.

+ References + Details

REVENUE FROM CONTRACT WITH CUSTOMERS (Tables)

3 Months Ended

Mar. 31, 2023

REVENUE FROM CONTRACT WITH CUSTOMERS

Schedule of Disaggregation of Revenue

The Company’s performance obligations are satisfied either over time or at a point-in-time. The following table represents a disaggregation of revenue percentage by timing of revenue:


	Three Months Ended March 31,
	2023		2022
Over time	80	%	70	%
Point-in-time	20	%	30	%
Total	100	%	100	%

BALANCE SHEET COMPONENTS (Tables)

3 Months Ended

Mar. 31, 2023

BALANCE SHEET COMPONENTS

Schedule of Property, Plant and Equipment

Property and equipment, net consist of the following (in thousands):


	March 31,		December 31,
	2023		2022
Computer equipment	$	11,930	$	11,853
Software		5,407		5,395
Furniture, fixtures, and equipment		2,488		2,484
Leasehold improvements		6,469		6,467
Laboratory and other equipment		4,494		4,431
Test equipment		28,403		28,403
Property and equipment in progress:
DFI™ system assets		23,596		22,231
CV® system and other assets		6,447		5,105
		89,234		86,369
Less: Accumulated depreciation and amortization		(47,511)		(46,195)
Total	$	41,723	$	40,174

Schedule of Finite-Lived Intangible Assets, Net

Intangible assets, net, consisted of the following (in thousands):


		March 31, 2023						December 31, 2022
	Amortization	Gross				Net		Gross				Net
	Period	Carrying		Accumulated		Carrying		Carrying		Accumulated		Carrying
	(Years)	Amount		Amortization		Amount		Amount		Amortization		Amount
Acquired identifiable intangibles:
Customer relationships	1-10	$	9,407	$	(6,845)	$	2,562	$	9,407	$	(6,684)	$	2,723
Developed technology	4-9		33,635		(20,244)		13,391		33,635		(19,647)		13,988
Tradename and trademarks	2-10		1,598		(945)		653		1,598		(918)		680
Patent	6-10		2,100		(1,717)		383		2,100		(1,696)		404
Noncompetition agreements	3		848		(660)		188		848		(588)		260
Total		$	47,588	$	(30,411)	$	17,177	$	47,588	$	(29,533)	$	18,055

Schedule of Finite-lived Intangible Assets Amortization Expense


	Three Months Ended March 31,
	2023		2022
Amortization of acquired technology included under Costs of Revenues	$	553	$	553
Amortization of acquired intangible assets presented separately under Costs and Expenses		325		314
Total amortization of acquired intangible assets	$	878	$	867

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

The Company expects annual amortization of acquired identifiable intangible assets to be as follows (in thousands):


Year Ending December 31,	Amount
2023 (remaining nine months)	$	2,613
2024		3,093
2025		2,928
2026		2,759
2027		2,606
2028 and thereafter		3,178
Total future amortization expense	$	17,177

There were no impairment charges for goodwill and intangible assets during the three months ended March 31, 2023 and 2022.

LEASES (Tables)

3 Months Ended

Mar. 31, 2023

LEASES

Schedule of Lease Expenses

Lease expense was comprised of the following (in thousands):


	Three Months Ended March 31,
	2023		2022
Operating lease expense (1)	$	387	$	345
Short-term lease and variable lease expense (2)		228		283
Total lease expense	$	615	$	628

(1)

Net of gain recognized upon lease termination of $0.1 million in the three months ended March 31, 2022.

(2)

Schedule of Supplemental Operating Lease Information

Supplemental condensed consolidated balance sheets information related to operating leases was as follows:


	March 31,			December 31,
	2023			2022
Weighted average remaining lease term under operating leases (in years)		5.1			5.3
Weighted average discount rate for operating lease liabilities		4.87	%		4.87	%

Schedule of Operating Lease Liabilities and Maturities

Maturities of operating lease liabilities as of March 31, 2023, were as follows (in thousands):


Year Ending December 31,	Amount (1)
2023 (remaining nine months)	$	1,299
2024		1,638
2025		1,551
2026		1,357
2027		1,294
2028 and thereafter		991
Total future minimum lease payments	$	8,130
Less: Interest (2)		(961)
Present value of future minimum lease payments under operating lease liabilities (3)	$	7,169

(1)

As of March 31, 2023, the total operating lease liability includes approximately $0.9 million related to an option to extend a lease term that is reasonably certain to be exercised.

(2)

Calculated using incremental borrowing interest rate for each lease.

(3)

Includes the current portion of operating lease liabilities of $1.6 million as of March 31, 2023.

EMPLOYEE BENEFIT PLANS (Tables)

3 Months Ended

Mar. 31, 2023

EMPLOYEE BENEFIT PLANS

Schedule of Share-based Payment Awards, Stock Options, Valuation Assumptions


	Three Months Ended March 31,
	2023			2022
Expected life (in years)		1.25			1.25
Volatility		46.70	%		48.90	%
Risk-free interest rate		4.48	%		0.86	%
Expected dividend		—			—
Weighted average fair value of purchase rights granted during the period	$	11.90		$	10.76

Schedule of Share-based Payment Arrangement, Expensed and Capitalized Amounts


	Three Months Ended March 31,
	2023		2022
Costs of revenues	$	964	$	728
Research and development		1,794		3,168
Selling, general, and administrative		2,126		1,657
Stock-based compensation expenses	$	4,884	$	5,553

Schedule of Share-based Payment Arrangement, Options Activity - Additional Information

Additional information with respect to options under the Stock Plans during the three months ended March 31, 2023, is as follows:


	Outstanding Options
				Weighted
		Weighted		Average
		Average		Remaining	Aggregate
	Number of	Exercise		Contractual	Intrinsic
	Options	Price		Term	Value
	(in thousands)	per Share		(Years)	(in thousands)
Outstanding, December 31, 2022	68	$	16.11
Granted	—		—
Exercised	(21)		16.42
Canceled	—		—
Expired	—		—
Outstanding, March 31, 2023	47	$	15.98	4.58	$	1,248
Vested and expected to vest, March 31, 2023	47	$	15.97	4.56	$	1,242
Exercisable, March 31, 2023	39	$	15.81	4.11	$	1,038

Schedule of Share-based Payment Arrangement, Restricted Stock Unit Activity

Nonvested restricted stock unit activity during the three months ended March 31, 2023, was as follows:


		Weighted
		Average Grant
	Shares	Date Fair Value
	(in thousands)	Per Share
Nonvested, December 31, 2022	2,124	$	21.29
Granted	46	$	33.46
Vested	(419)	$	20.62
Forfeited	(3)	$	19.69
Nonvested, March 31, 2023	1,748	$	21.78

NET LOSS PER SHARE (Tables)

3 Months Ended

Mar. 31, 2023

NET LOSS PER SHARE

Schedule of Earnings Per Share, Basic and Diluted


	Three Months Ended March 31,
	2023		2022
Numerator:
Net income (loss)	$	355	$	(4,150)
Denominator:
Basic weighted average shares outstanding		37,737		37,606
Effect of dilutive stock options, unvested restricted stock units, and shares of common stock expected to be issued under Employee Purchase Plans		1,122		—
Diluted weighted average shares outstanding		38,859		37,606

Net income (loss) per share:
Basic	$	0.01	$	(0.11)
Diluted	$	0.01	$	(0.11)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share


	Three Months Ended March 31,
	2023	2022
Outstanding options	—	102
Non-vested restricted stock units	9	905
Employee Stock Purchase Plan	—	94
Total	9	1,101

CUSTOMER AND GEOGRAPHIC INFORMATION (Tables)

3 Months Ended

Mar. 31, 2023

CUSTOMER AND GEOGRAPHIC INFORMATION

Schedule of Revenue by Major Customers by Reporting Segments

Revenues from an individual customer that are approximately 10% or more of the Company’s consolidated total revenues are as follows:


	Three Months Ended March 31,
Customer	2023		2022
A	38	%	33	%


	March 31,		December 31,
Customer	2023		2022
A	42	%	29	%
B	10	%	12	%
C	*	%	12	%

* represents less than 10%

Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area

Revenues from customers by geographic area based on the location of the customers’ work sites are as follows (amounts in thousands):


	Three Months Ended March 31,
	2023				2022
			Percentage				Percentage
	Revenues		of Revenues		Revenues		of Revenues
United States	$	23,274	57	%	$	17,491	52	%
China		6,956	17			4,120	12
Rest of the world		10,529	26			11,887	36
Total revenue	$	40,759	100	%	$	33,498	100	%

Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country

Long-lived assets, net by geographic area are as follows (in thousands):


	March 31,		December 31,
	2023		2022
United States (1)	$	46,137	$	44,730
Rest of the world		1,298		1,446
Total long-lived assets, net	$	47,435	$	46,176

(1) Includes assets deployed at customer sites which could be outside the U.S.

FAIR VALUE MEASUREMENTS (Tables)

3 Months Ended

Mar. 31, 2023

FAIR VALUE MEASUREMENTS

Schedule of Fair Value, Assets Measured on Recurring Basis

The following table represents the Company’s assets measured at fair value on a recurring basis as of March 31, 2023, and December 31, 2022, and the basis for those measurements (in thousands):


	Fair Value Measurements Using
			Quoted
			Prices in
			Active		Significant
			Markets for		Other
			Identical		Observable		Significant
	March 31,		Assets		Inputs		Unobservable
Assets	2023		(Level 1)		(Level 2)		Inputs (Level 3)
Cash equivalents
Money market mutual funds	$	76,204	$	76,204	$	—	$	—
U.S. Government securities (1)		2,999		2,999		—		—
Short-term investments (available-for-sale debt securities)
U.S. Government securities (1)		19,146		19,146		—		—
Total	$	98,349	$	98,349	$	—	$	—


	Fair Value Measurements Using
			Quoted
			Prices in
			Active		Significant
			Markets for		Other		Significant
			Identical		Observable		Unobservable
	December 31,		Assets		Inputs		Inputs
Assets	2022		(Level 1)		(Level 2)		(Level 3)
Cash equivalents
Money market mutual funds	$	75,738	$	75,738	$	—	$	—
U.S. Government securities (1)		1,990		1,990		—		—
Short-term investments (available-for-sale debt securities)
U.S. Government securities (1)		19,557		19,557		—		—
Total	$	97,285	$	97,285	$	—	$	—

(1)

REVENUE FROM CONTRACT WITH CUSTOMERS (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023 USD ($) item	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Number of revenue sources \| item	2
Contract with Customer, Asset, after Allowance for Credit Loss, Current, Total	$ 2,900		$ 3,300
Capitalized Contract Cost, Impairment Loss	0	$ 0	0
Revenue, Remaining Performance Obligation, Amount	261,200
Contract with Customer, Performance Obligation Satisfied in Previous Period	2,500	200
Capitalized Contract Cost, Amortization	456	173
Prepaid Expenses and Other Current Assets
Capitalized Contract Cost, Net, Total	1,800		1,700
Other Non-current Assets
Capitalized Contract Cost, Net, Total	3,200		$ 2,100
Non-current Liabilities
Contract with Customer, Liability, Revenue Deferred	2,300	1,900
Deferred Revenue and Billings in Excess of Recognized Revenue
Contract with Customer, Liability, Revenue Recognized	$ 11,400	$ 6,900
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member]
Percentage of Revenues	100.00%	100.00%
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member] \| Non-US [Member]
Percentage of Revenues	43.00%	48.00%

REVENUE FROM CONTRACT WITH CUSTOMERS - Disaggregation of Revenue (Details)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Percent of revenues	100.00%	100.00%
Transferred over Time [Member]
Percent of revenues	80.00%	70.00%
Transferred at Point in Time [Member]
Percent of revenues	20.00%	30.00%

REVENUE FROM CONTRACT WITH CUSTOMERS - Additional information (Details)	Mar. 31, 2023
Software License and Related Services Agreement [Member] \| Advantest America, Inc. [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01
Revenue recognition, expected period to recognize more than half of remaining performance obligations	2 years

STRATEGIC PARTNERSHIP AGREEMENT WITH ADVANTEST AND RELATED PARTY TRANSACTIONS (Details)			3 Months Ended
	Oct. 31, 2022 USD ($)	Jul. 29, 2020 USD ($) shares	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Strategic Partnership for Joint Development and Sales Technology Solutions
Stock Issued During Period, Shares, New Issues (in shares) \| shares		3,306,924
Proceeds from Issuance of Common Stock		$ 65,200,000
Amendment #1 to Software License & Related Services Agreement
Commitments from Advantest	$ 50,000,000.0
Commercial Agreement With Advantest
Related party receivables			$ 0		$ 300,000
Number contract termination events			0
Commercial Agreement With Advantest \| Analytics
Advantest analytics revenue			$ 1,800,000	$ 2,600,000
Deferred revenue			$ 5,900,000		$ 7,100,000

BALANCE SHEET COMPONENTS (Details) - USD ($)	3 Months Ended
BALANCE SHEET COMPONENTS (Details) - USD ($)	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Unbilled Receivables, Current	$ 16,100,000		$ 13,500,000
Unbilled Receivables, Not Expected to be Billed and Collected in Next Twelve Months	700,000		800,000
Depreciation, Depletion and Amortization, Nonproduction, Total	1,300,000	$ 1,400,000
Impairment of Intangible Assets, Finite-lived	0	0
Goodwill	14,123,000		$ 14,123,000
Impairment of goodwill	0	0
Amortization of Intangible Assets, Total	$ 878,000	867,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)	5 years 8 months 12 days
Costs of Revenues
Amortization of Intangible Assets, Total	$ 553,000	553,000
Costs and Expenses [Member]
Amortization of Intangible Assets, Total	$ 325,000	$ 314,000

BALANCE SHEET COMPONENTS - Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Property and equipment, gross	$ 89,234	$ 86,369
Less: accumulated depreciation and amortization	(47,511)	(46,195)
Total	41,723	40,174
Computer Equipment
Property and equipment, gross	11,930	11,853
Software
Property and equipment, gross	5,407	5,395
Furniture, Fixtures and Equipment
Property and equipment, gross	2,488	2,484
Leasehold Improvements
Property and equipment, gross	6,469	6,467
Laboratory and Other Equipment
Property and equipment, gross	4,494	4,431
Test Equipment
Property and equipment, gross	28,403	28,403
In-Progress DFI System Assets
Property and equipment, gross	23,596	22,231
In-Progress CV System and Other Assets
Property and equipment, gross	$ 6,447	$ 5,105

BALANCE SHEET COMPONENTS - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Amortization Period (Year)	5 years 8 months 12 days
Gross Carrying Amount	$ 47,588	$ 47,588
Accumulated Amortization	(30,411)	(29,533)
Total future amortization expense	17,177
Net Carrying Amount, Total	17,177	18,055
Customer Relationships [Member]
Gross Carrying Amount	9,407	9,407
Accumulated Amortization	(6,845)	(6,684)
Total future amortization expense	$ 2,562	2,723
Customer Relationships [Member] \| Minimum [Member]
Amortization Period (Year)	1 year
Customer Relationships [Member] \| Maximum [Member]
Amortization Period (Year)	10 years
Developed Technology Rights [Member]
Gross Carrying Amount	$ 33,635	33,635
Accumulated Amortization	(20,244)	(19,647)
Total future amortization expense	$ 13,391	13,988
Developed Technology Rights [Member] \| Minimum [Member]
Amortization Period (Year)	4 years
Developed Technology Rights [Member] \| Maximum [Member]
Amortization Period (Year)	9 years
Trademarks and Trade Names [Member]
Gross Carrying Amount	$ 1,598	1,598
Accumulated Amortization	(945)	(918)
Total future amortization expense	$ 653	680
Trademarks and Trade Names [Member] \| Minimum [Member]
Amortization Period (Year)	2 years
Trademarks and Trade Names [Member] \| Maximum [Member]
Amortization Period (Year)	10 years
Patents [Member]
Gross Carrying Amount	$ 2,100	2,100
Accumulated Amortization	(1,717)	(1,696)
Total future amortization expense	$ 383	404
Patents [Member] \| Minimum [Member]
Amortization Period (Year)	6 years
Patents [Member] \| Maximum [Member]
Amortization Period (Year)	10 years
Noncompete Agreements [Member]
Amortization Period (Year)	3 years
Gross Carrying Amount	$ 848	848
Accumulated Amortization	(660)	(588)
Total future amortization expense	$ 188	$ 260

BALANCE SHEET COMPONENTS - Annual Amortization of Identifiable Intangible Assets (Details) $ in Thousands	Mar. 31, 2023 USD ($)
BALANCE SHEET COMPONENTS
2023 (remaining nine months)	$ 2,613
2024	3,093
2025	2,928
2026	2,759
2027	2,606
2028 and thereafter	3,178
Total future amortization expense	$ 17,177

LEASES - Other (Details) $ in Thousands	3 Months Ended
LEASES - Other (Details) $ in Thousands	Mar. 31, 2023 USD ($) lease	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) lease
LEASES
Number of finance leases \| lease	0		0
Operating Lease, Liability, Amount Related to Extension of Lease Term	$ 900
Operating Lease, Liability, Current	1,572		$ 1,412
Operating lease right of use assets decrease from early lease termination		$ 500
Operating lease liability decrease from early lease termination		$ 600
Lease termination gain	$ 100

LEASES - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
LEASES - Lease Cost (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
LEASES
Operating lease expense	$ 387	$ 345
Short-term lease and variable lease expense	228	283
Total lease expense	615	$ 628
Lease termination gain	$ 100
Weighted average remaining lease term under operating ROU leases (in years) (Year)	5 years 1 month 6 days		5 years 3 months 18 days
Weighted average discount rate for operating lease liabilities	4.87%		4.87%

LEASES - Maturity of Operating Lease Liabilities (Details) $ in Thousands	Mar. 31, 2023 USD ($)
LEASES
2023 (remaining nine months)	$ 1,299
2024	1,638
2025	1,551
2026	1,357
2027	1,294
2028 and thereafter	991
Total future minimum lease payments	8,130
Less: Interest (2)	(961)
Present value of future minimum lease payments under operating lease liabilities (3)	$ 7,169

STOCKHOLDERS EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		12 Months Ended	34 Months Ended
	Apr. 11, 2022	Jun. 04, 2020	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2023
Treasury Stock, Value, Acquired, Cost Method			$ 4,101	$ 3,389
The 2020 Stock Repurchase Program [Member]
Stock Repurchase Program, Authorized Amount		$ 25,000
Stock Repurchase Program, Period in Force (Year)		2 years
Common stock repurchased				218,858		470,070
Repurchase of common stock, weighted-average price per share				$ 26.40		$ 21.91
Repurchases of common stock, cost				$ 5,800		$ 10,300
Stock Repurchase Program 2022 [Member]
Stock Repurchase Program, Authorized Amount	$ 35,000
Stock Repurchase Program, Period in Force (Year)	2 years
Common stock repurchased					714,600
Repurchase of common stock, weighted-average price per share					$ 23.36
Repurchases of common stock, cost					$ 16,700

EMPLOYEE BENEFIT PLANS - Other (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended		12 Months Ended	131 Months Ended	227 Months Ended
	Jun. 15, 2021	Nov. 16, 2011	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Sep. 30, 2022	May 16, 2020	Apr. 24, 2023
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)			47,000		68,000
Share Price (in dollars per share)			$ 42.40
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 0.4
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			$ 30.2
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years 6 months
Shares Previously Issued Under the 2001 Plan
Number Of ESPP Shares Available For Future Issuance (in shares)		3,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Cumulative Forfeitures of Plan (in shares)						500,000
Outside of the 2011, 2001 or IDS Plans
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)			0
The 2011 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)		12,800,000
Share Based Compensation Arrangement By Share Based Payment Award Shares Reserved Decrease Rate (in shares)		1.33
Common Stock, Capital Shares Reserved for Future Issuance (in shares)			13,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)			3,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)			0	0	0
The 2011 Stock Incentive Plan \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)		4 years
The 2011 Stock Incentive Plan \| Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)								13,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Period Increase in Shares Authorized								1,000,000.0
The 2010 Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate							10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent							85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Offering Period							24 months
Number of 6-month Offering Periods							4
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Period							6 months
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)				5,203
Employee Stock Purchase Plan Weighted Average Purchase Price of Shares Purchased (in dollars per share)				$ 13.40
The 2021 Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Offering Period	24 months
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)			98,216	90,040
Employee Stock Purchase Plan Weighted Average Purchase Price of Shares Purchased (in dollars per share)			$ 16.93	$ 15.90
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			$ 1.0
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 1 month 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years
Common Stock, Capital Shares Reserved for Future Issuance (in shares)			719,701
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)			4 years

EMPLOYEE BENEFIT PLANS - Valuation Assumptions for ESPP (Details) - The 2021 Purchase Plan - $ / shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Expected life (in years) (Year)	1 year 3 months	1 year 3 months
Volatility	46.70%	48.90%
Risk-free interest rate	4.48%	0.86%
Expected dividend	0.00%
Weighted average fair value of purchase rights granted during the period (in dollars per share)	$ 11.90	$ 10.76

EMPLOYEE BENEFIT PLANS - Allocation of Recognized Period Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Stock-based compensation expenses	$ 4,884	$ 5,553
Costs of Revenues
Stock-based compensation expenses	964	728
Research and Development Expense [Member]
Stock-based compensation expenses	1,794	3,168
Selling, General and Administrative Expenses [Member]
Stock-based compensation expenses	$ 2,126	$ 1,657

EMPLOYEE BENEFIT PLANS - Stock Options Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($) $ / shares shares
EMPLOYEE BENEFIT PLANS
Outstanding, beginning balance (in shares) \| shares	68
Exercised (in shares) \| shares	(21)
Outstanding, ending balance (in shares) \| shares	47
Vested and expected to vest (in shares) \| shares	47
Exercisable (in shares) \| shares	39
Outstanding, weighted average exercise price, beginning balance (in dollars per share) \| $ / shares	$ 16.11
Exercised, weighted average exercise price (in dollars per share) \| $ / shares	16.42
Outstanding, weighted average exercise price, ending balance (in dollars per share) \| $ / shares	15.98
Vested and expected to vest, weighted average exercise price (in dollars per share) \| $ / shares	15.97
Exercisable, weighted average exercise price (in dollars per share) \| $ / shares	$ 15.81
Outstanding, weighted average remaining contractual (Year)	4 years 6 months 29 days
Vested and expected to vest, weighted average remaining contractual term (Year)	4 years 6 months 21 days
Exercisable, weighted average remaining contractual term (Year)	4 years 1 month 9 days
Outstanding, aggregate intrinsic value \| $	$ 1,248
Vested and expected to vest, aggregate intrinsic value \| $	1,242
Exercisable, aggregate intrinsic value \| $	$ 1,038

EMPLOYEE BENEFIT PLANS - Nonvested Restricted Stock Units Activity (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2023 $ / shares shares
Nonvested, Opening Balance (in shares) \| shares	2,124
Nonvested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 21.29
Restricted Stock Units (RSUs) [Member]
Granted (in shares) \| shares	46
Vested (in shares) \| shares	(419)
Forfeited (in shares) \| shares	(3)
Nonvested, Ending Balance (in shares) \| shares	1,748
Granted, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 33.46
Vested, weighted average grant date fair value (in dollars per share) \| $ / shares	20.62
Forfeited, weighted average grant date fair value (in dollars per share) \| $ / shares	19.69
Nonvested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 21.78

INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended
INCOME TAXES (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
INCOME TAXES
Increase (Decrease) in Income Taxes	$ 800
Income Tax Expense (Benefit), Total	$ 390	$ 1,187
Effective Income Tax Rate Reconciliation, Percent, Total	52.00%	40.00%
Unrecognized Tax Benefits, Ending Balance	$ 15,200		$ 15,100
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	2,000		2,000
Unrecognized tax benefits including income tax penalties and interest accrued in long term liabilities	2,600
Unrecognized tax benefits related to income tax penalties and interest accrued in long-term liabilities	700
Unrecognized Tax Benefits In Deferred Tax Assets	13,200
Deferred Tax Assets, Valuation Allowance, Total	$ 59,200		$ 59,200

NET LOSS PER SHARE - Calculation of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
NET LOSS PER SHARE
Net loss	$ 355	$ (4,150)
Basic weighted-average shares outstanding (in shares)	37,737	37,606
Effect of dilutive options and restricted stock units (in shares)	1,122
Diluted weighted-average shares outstanding (in shares)	38,859	37,606
Basic (in dollars per share)	$ 0.01	$ (0.11)
Diluted (in dollars per share)	$ 0.01	$ (0.11)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 65
-Paragraph 1
-Subparagraph (e)(4)
-URI https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-Subparagraph (b)
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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

NET LOSS PER SHARE - Anti-dilutive Securities (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Anti-dilutive securities (in shares)	9	1,101
Share-based Payment Arrangement, Option [Member]
Anti-dilutive securities (in shares)		102
Restricted Stock Units (RSUs) [Member]
Anti-dilutive securities (in shares)	9	905
Employee Stock Purchase Plan
Anti-dilutive securities (in shares)		94

CUSTOMER AND GEOGRAPHIC INFORMATION - Other (Details)	3 Months Ended
CUSTOMER AND GEOGRAPHIC INFORMATION - Other (Details)	Mar. 31, 2023
CUSTOMER AND GEOGRAPHIC INFORMATION
Number of Operating Segments	1
Number of Reportable Segments	1

CUSTOMER AND GEOGRAPHIC INFORMATION - Revenue Percentage by Major Customers (Details) - Customer Concentration Risk [Member]	3 Months Ended		12 Months Ended	15 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Mar. 31, 2023
Revenue Benchmark [Member] \| Benchmark Percentage of Gross Revenues and Receivables
Concentration risk				10.00%
Revenue Benchmark [Member] \| Customer A [Member]
Concentration risk	38.00%	33.00%
Accounts Receivable [Member] \| Benchmark Percentage of Gross Revenues and Receivables
Concentration risk				10.00%
Accounts Receivable [Member] \| Customer A [Member]
Concentration risk	42.00%		29.00%
Accounts Receivable [Member] \| Customer B [Member]
Concentration risk	10.00%		12.00%
Accounts Receivable [Member] \| Customer C [Member]
Concentration risk			12.00%

CUSTOMER AND GEOGRAPHIC INFORMATION - Revenues by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenues	$ 40,759	$ 33,498
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member]
Revenues	$ 40,759	$ 33,498
Percentage of Revenues	100.00%	100.00%
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member] \| UNITED STATES
Revenues	$ 23,274	$ 17,491
Percentage of Revenues	57.00%	52.00%
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member] \| CHINA
Revenues	$ 6,956	$ 4,120
Percentage of Revenues	17.00%	12.00%
Geographic Concentration Risk [Member] \| Revenue Benchmark [Member] \| Rest of the World
Revenues	$ 10,529	$ 11,887
Percentage of Revenues	26.00%	36.00%

- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details

CUSTOMER AND GEOGRAPHIC INFORMATION - Long-lived Assets by Geographic Area (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Long-lived assets, net	$ 47,435	$ 46,176
UNITED STATES
Long-lived assets, net	46,137	44,730
Rest of the World
Long-lived assets, net	$ 1,298	$ 1,446

FAIR VALUE MEASUREMENTS - Fair Value, Assets Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Total	$ 98,349	$ 97,285
Quoted Prices in Active Markets for Identical Assets (level 1)
Total	98,349	97,285
Money Market Mutual Funds
Cash equivalents	76,204	75,738
Money Market Mutual Funds \| Quoted Prices in Active Markets for Identical Assets (level 1)
Cash equivalents	76,204	75,738
US Government Securities
Cash equivalents	2,999	1,990
Short-term investments (available-for-sale debt securities)	19,146	19,557
US Government Securities \| Quoted Prices in Active Markets for Identical Assets (level 1)
Cash equivalents	2,999	1,990
Short-term investments (available-for-sale debt securities)	$ 19,146	$ 19,557

COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	3 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Mar. 31, 2023 USD ($)
COMMITMENTS AND CONTINGENCIES
Future Lease payments	$ 8,130
Term of Product Warranty	90 days
Purchase Obligation, Total	$ 25,700
Threshold payment period	24 months