Note 10 — Commitments and Contingencies

Warranty

Changes in the Company’s product warranty reserves were as follows:

December 31,

  ​ ​ ​

2025

  ​ ​ ​

2024

  ​ ​ ​

2023

(in thousands)

Balance - beginning of the year

$

9,740

$

8,864

$

8,601

Warranties issued

 

7,262

 

6,160

 

6,479

Addition from Epiluvac acquisition

49

Consumption of reserves

 

(5,422)

 

(6,148)

 

(7,029)

Changes in estimate

 

(1,232)

 

864

 

764

Balance - end of the year

$

10,348

$

9,740

$

8,864

Minimum Lease Commitments

The Company’s operating leases primarily include real estate leases for properties used for manufacturing, R&D activities, sales and service, and administration, as well as certain equipment leases. Some leases may include options to renew for a period of up to 5 years, while others may include options to terminate the lease. The weighted average remaining lease term of the Company’s operating leases as of December 31, 2025 was 10 years, and the weighted average discount rate used in determining the present value of future lease payments was 5.7%.

The following table provides the maturities of lease liabilities at December 31, 2025:

Operating

  ​ ​ ​

Leases

(in thousands)

Payments due by period:

2026

$

4,671

2027

4,883

2028

4,440

2029

4,302

2030

4,077

Thereafter

26,539

Total future minimum lease payments

48,912

Less: Imputed interest

(12,911)

Total

$

36,001

Reported as of December 31, 2025

Accrued expenses and other current liabilities

$

4,164

Long-term operating lease liabilities

31,837

Total

$

36,001

Operating lease cost for the years ended December 31, 2025, 2024, and 2023 was $5.0 million, $4.8 million, and $5.0 million, respectively. Variable lease expense, which includes costs not included in the operating lease costs, for the years ended December 31, 2025, 2024, and 2023 was $1.1 million, $1.3 million, and $1.1 million, respectively. Additionally, the Company has an immaterial amount of short-term leases. Lease expense, which includes operating lease costs and variable lease costs, was $6.1 million for the years ended December 31, 2025, 2024, and 2023, respectively. In addition, the Company is obligated under such leases for certain other expenses, including real estate taxes and insurance. Operating cash outflows from operating leases for the year ended December 31, 2025, 2024, and 2023 were $7.2 million, $6.8 million, and $5.8 million, respectively.

Legal Proceedings

The Company is involved in various legal proceedings arising in the normal course of business. The Company does not believe that the ultimate resolution of these matters will have a material adverse effect on its consolidated financial position, results of operations, or cash flows.

Concentrations of Credit Risk

The Company depends on purchases from its ten largest customers, which accounted for 68% and 63% of net accounts receivable at December 31, 2025 and 2024, respectively.

Customers who accounted for more than 10% of net accounts receivable or net sales are as follows:

Accounts Receivable

Net Sales 

 

December 31,

For the Year Ended December 31,

 

Customer

  ​ ​ ​

2025

  ​ ​ ​

2024

  ​ ​ ​

2025

  ​ ​ ​

2024

  ​ ​ ​

2023

 

Customer A

24

%

13

%

17

%

11

%

*

Customer B

*

11

%

*

11

%

*

Customer C

*

13

%

*

*

*

Customer D

*

11

%

*

*

*

Customer E

 

*

*

*

*

10

%

*

Less than 10% of aggregate accounts receivable or net sales

The Company manufactures and sells its products to companies in different geographic locations. Refer to Note 16, “Segment Reporting and Geographic Information,” for additional information. In certain instances, the Company requires deposits from its customers for a portion of the sales price in advance of shipment and performs periodic credit evaluations on its customers. Where appropriate, the Company requires letters of credit on certain non-U.S. sales arrangements. Receivables generally are due within 30 to 90 days from the date of invoice. In some geographies, receivables may be payable up to 150 days from the date of the invoice.

Receivable Purchase Agreement

The Company entered into a receivable purchase agreement with a financial institution to sell certain of its trade receivables from customers without recourse, up to $30.0 million at any point in time. Pursuant to this agreement, the Company sold no receivables during the year ended December 31, 2025, and $30.0 million was available under the agreement for additional sales of receivables. The Company sold $8.0 million of receivables during the year ended December 31, 2024. The net sale of accounts receivable under the agreement is reflected as a reduction of accounts receivable in the Company’s Consolidated Balance Sheet at the time of sale and any fees for the sale of trade receivables were not material for the periods presented.

Suppliers

The Company outsources certain functions to third parties, including the manufacture of several of its systems. While the Company relies on its outsourcing partners to perform their contracted functions, the Company maintains some level of internal manufacturing capability for these systems. In addition, certain of the components and sub-assemblies included in the Company’s products are obtained from a single source or a limited group of suppliers. The failure of the Company’s present outsourcing partners and suppliers to meet their contractual obligations and the Company’s inability to make alternative arrangements or resume the manufacture of these systems could have a material adverse effect on the Company’s revenues, profitability, cash flows, and relationships with its customers.

The Company had deposits with its suppliers of $9.8 million and $18.7 million at December 31, 2025 and 2024, respectively, that were included in “Prepaid expenses and other current assets” on the Consolidated Balance Sheets.

Purchase Commitments

The Company had purchase commitments of $150.8 million at December 31, 2025, the majority of which will come due within one year. Purchase commitments are primarily for inventory used in manufacturing products, as well as equipment and project materials used to support research and development activities, and are partially offset by existing deposits with suppliers.

Bank Guarantees

The Company has bank guarantees and letters of credit issued by a financial institution on its behalf as needed. At December 31, 2025, outstanding bank guarantees and letters of credit totaled $2.4 million and unused bank guarantees and letters of credit of $40.6 million were available to be drawn upon.

About Commitments Disclosures

Commitments and contingencies disclosures catalog a company's off-balance-sheet obligations and legal exposures — purchase commitments, guarantee arrangements, pending litigation, and regulatory proceedings. These items represent potential future cash outflows that may not appear as liabilities on the balance sheet until they become probable and estimable.

Key signals: litigation reserves and disclosed loss ranges quantify management's estimate of legal exposure, but unquantified "reasonably possible" losses often represent the larger risk. Watch for changes in language around pending cases — shifts from "remote" to "reasonably possible" or increases in estimated loss ranges signal deteriorating outcomes. Unconditional purchase obligations and take-or-pay contracts create fixed cost structures that reduce operational flexibility. Guarantee arrangements for subsidiaries or joint ventures can create cascading obligations. Compare the total commitment schedule against projected free cash flow to assess whether the company can meet its obligations without additional financing.