MacLean Michael F 4

What Happened
Michael F. MacLean, Chief Financial Officer of Avidity Biosciences (RNA), sold a total of 4,542 shares of company stock in two open-market transactions on January 21, 2026. The shares were sold at $72.45 each for a combined proceeds of approximately $329,068. These sales were disposals (not purchases) and were executed as sell-to-cover transactions tied to RSU vesting.

Key Details

• Transaction dates and prices: 1,807 shares sold on 2026-01-21 at $72.45 ($130,917 reported) and 2,735 shares sold on 2026-01-21 at $72.45 ($198,151 reported). Total ~4,542 shares, ~$329,068.
• Reason/footnote: Sales were required to cover tax withholding for RSUs that vested on 2026-01-20; the issuer’s plan mandates sell-to-cover. Reporting person executed an instruction letter and the sale was intended to meet the affirmative defense conditions of Rule 10b5-1.
• Shares owned after transaction: Not specified in the provided transaction summary.
• Filing timeliness: Form filed 2026-01-23 for transactions on 2026-01-21 (timely filing).

Context
Sell-to-cover transactions are routine administrative sales to satisfy tax obligations on vested restricted stock units and are not discretionary trades indicating a change in the insider’s view of the company. The mention of a pre-arranged instruction and Rule 10b5-1 language reinforces that these sales were procedural rather than opportunistic.