X0306 4 2021-12-14 0001001385 NORTHWEST PIPE CO NWPX 0001228503 MONTROSS SCOTT J 201 NE PARK PLAZA DRIVE SUITE 100 VANCOUVER WA 98684 1 President & CEO Common Stock 2021-12-14 4 S 0 200 30 D 87154 D Common Stock 2021-12-15 4 S 0 200 30.0004 D 86954 D Restricted Stock Common Stock 14873 14873 D Performance Shares Common Stock 36187 36187 D Sale of stock pursuant to a 10b5-1 trading plan previously adopted by the Reporting Person. This transaction was executed in multiple trades at prices ranging from $30.00 to $30.01 per share. The price reported reflects the weighted average sale price. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or to the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. Each Restricted Stock Unit represents a contingent right to receive one share of Northwest Pipe Company common stock. The Restricted Stock Units vest in installments in January of 2022, 2023 and 2024. Performance Shares vest in an amount ranging from 0-200% to the extent such Performance Shares are earned. Performance Shares are earned based on Northwest Pipe Company's total EBITDA margin over the measurement period. The Performance Shares vest in installments in March of 2022, 2023 and 2024. /s/ Megan Kendrick 2021-12-16