X0508 4 2023-08-16 0 0000355948 RICHARDSON ELECTRONICS, LTD. RELL 0001291981 Diddell Wendy 40W267 KESLINGER ROAD PO BOX 393 LAFOX IL 60147 1 1 0 0 COO 0 Common Stock 2023-08-16 4 M 0 1919 7.66 A 107391 D Common Stock 2023-08-16 4 S 0 1919 12.0513 D 105472 D Common Stock 2023-08-16 4 S 0 1817 12.08 D 103655 D Employee Stock Option (Right to Buy) 7.66 2023-08-16 4 M 0 1919 0.00 D 2031-07-19 Common Stock 1919 1795 D The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $12.00 to $12.09 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $12.00 to $12.135 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. Options vest 20% per year, beginning 07/19/2022 /s/ Robert J. Ben, attorney-in-fact for Wendy Diddell 2023-08-18