NORTHWEST PIPE CO

During thethree months ended* June* 30, 2024, none of our directors or officers adopted, modified, or terminated a Rule10b5‑1 trading arrangement or a non-Rule10b5‑1 trading arrangement, as such terms are defined under Item408(a) of Regulation S‑K, except as follows:

On* May31,* 2024*,* Megan Kendrick, our Vice President of Human Resources, adopted a Rule10b5‑1 trading arrangement for the sale of shares of our common stock, which is intended to satisfy the affirmative defense conditions of Rule10b5‑1(c) under the Exchange Act. Ms. Kendrick’s Rule10b5‑1 trading arrangement provides for the potential sale of up to 2,000 shares of our common stock between* September15,* 2024 and* December31,* 2024, so long as the market price of our common stock is higher than certain minimum threshold prices specified in Ms. Kendrick’s Rule10b5‑1 trading arrangement.

On* June5,* 2024*,* Miles Brittain, our Executive Vice President, adopted a Rule10b5‑1 trading arrangement for the sale of shares of our common stock, which is intended to satisfy the affirmative defense conditions of Rule10b5‑1(c) under the Exchange Act. Mr. Brittain’s Rule10b5‑1 trading arrangement provides for the potential sale of up to 4,500 shares of our common stock between* September4,* 2024 and* June6,* 2025, so long as the market price of our common stock is higher than certain minimum threshold prices specified in Mr. Brittain’s Rule10b5‑1 trading arrangement.

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