TERADYNE INC

10b 5-1 Trading Plans

Our officers (as defined in Rule 16a-1(f) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) (“Section 16 Officers”) and directors from time to time enter into contracts, instructions or written plans for the purchase or sale of our securities that are intended to satisfy the conditions specified in Rule 10b5-1(c) under the Exchange Act for an affirmative defense against liability for trading in securities on the basis of material nonpublic information. We refer to these contracts, instructions, and written plans as “Rule 10b5-1 trading plans” and each one as a “Rule 10b5-1 trading plan.” During our fiscal quarter ended March 31, 2024, the following Section 16 Officers or directors adopted, modified or terminated Rule 10b5-1 trading plans:

Richard Burns, President, Semiconductor Test

Richard Burns, our President, Semiconductor Test, entered into a new Rule 10b5-1 trading plan on February 15, 2024. The Rule 10b5-1 trading plan provides that Mr. Burns, acting through a broker, may sell up to an aggregate of (i) 50% of the (net) shares resulting from the vesting of 10,759 (gross) restricted stock units (net shares are net of tax withholding), and (ii) 100% of the (net) shares resulting from the exercise of up to 8,700 stock options (net shares are net of the stock option exercise prices). Subject to price limits, the first trade under Mr. Burns’s Rule 10b5-1 trading plan is scheduled for May 20, 2024. Mr. Burns’s plan is scheduled toterminate on February 28, 2025, subject to earlier termination upon the sale of all shares subject to the plan, upon termination by Mr. Burns or the broker, or as otherwise provided in the plan.

Mercedes Johnson, Director

Mercedes Johnson, amember of our Board of Directors, entered into a new Rule 10b5-1 trading plan on February 2, 2024. The Rule 10b5-1 trading plan provides that Ms. Johnson, acting through a broker, may sell up to an aggregate of 7,500 shares. Subject to price limits, the first trade under Ms. Johnson’s Rule 10b5-1 trading plan is scheduled for June 3, 2024. Ms. Johnson’s plan is scheduled toterminate on April 30, 2025, subject to earlier termination upon the sale of all shares subject to the plan, upon termination by Ms. Johnson or the broker, or as otherwise provided in the plan.