ONTO INNOVATION INC. Fair Value Disclosure

Fair Value of Financial Instruments

The Company has evaluated the estimated fair value of financial instruments using available market information and valuations as provided by third-party sources. The use of different market assumptions and/or estimation methodologies could have a significant effect on the estimated fair value amounts. The carrying value of cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities approximates fair value because of the short-term maturity of these instruments.

Fair Value Hierarchy

The Company applies a three-level valuation hierarchy for fair value measurements. This hierarchy prioritizes the inputs into three broad levels. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the asset or liability, either directly or indirectly through market corroboration, for substantially the full term of the asset or liability. Level 3 inputs are unobservable inputs based on management’s assumptions used to measure assets and liabilities at fair value. A financial asset’s or liability’s fair value measurement classification within the hierarchy is determined based on the lowest level input that is significant to the fair value measurement.

Available-for-sale debt securities classified as Level 2 are valued using observable inputs to quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. The foreign currency forward contracts are primarily measured based on the foreign currency spot and forward rates quoted by the banks or foreign currency dealers. Available-for-sale debt securities prices are obtained from third party pricing providers, which model prices utilizing the above observable inputs, for each asset class.

See Note 5 for additional discussion regarding the fair value of the Company’s marketable securities.

Non-recurring Fair Value Measurements

During the fiscal year ended January 3, 2026, the Company invested $8.0 million in the equity of a privately-held company. There were no such investments at December 28, 2024. This non-marketable equity investment is recorded at fair value on a non-recurring basis and is classified as a Level 3 asset in “Other assets” on the Condensed Consolidated Balance Sheets. This non-marketable equity investment is generally accounted for under the measurement alternative, defined as cost, less impairments, adjusted for subsequent observable price changes and is periodically assessed for impairment when events or circumstances indicate that decline in value may have occurred. As of January 3, 2026, there have been no impairments recorded for the non-marketable equity investment.