Eric Mosbrooker - 17 Dec 2025 Form 4 Insider Report for Avidity Biosciences, Inc. (RNA)

Signature
/s/ John B. Moriarty, Jr., J.D., Attorney-in-Fact
Issuer symbol
RNA
Transactions as of
17 Dec 2025
Net transactions value
-$3,449,041
Form type
4
Filing time
19 Dec 2025, 08:29:16 UTC
Previous filing
07 Oct 2025
Next filing
27 Feb 2026

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Mosbrooker Eric Chief Commercial Officer C/O AVIDITY BIOSCIENCES, INC., 3020 CALLAN RD., SAN DIEGO /s/ John B. Moriarty, Jr., J.D., Attorney-in-Fact 19 Dec 2025 0001715283

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction RNA Common Stock Award $0 +72,000 +131% $0.000000 127,000 17 Dec 2025 Direct F1
transaction RNA Common Stock Tax liability $2,627,855 -36,564 -29% $71.87 90,436 17 Dec 2025 Direct F2
transaction RNA Common Stock Tax liability $821,187 -11,426 -13% $71.87 79,010 17 Dec 2025 Direct F3
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Represents shares acquired upon the vesting of performance-based restricted stock units (PSUs). Each PSU represented a contingent right to receive one share of the Issuer's common stock. The PSUs were originally granted to the Reporting Person on October 30, 2024. The PSUs were accelerated and settled on December 17, 2025 for tax planning purposes and such shares remain subject to recoupment by the Issuer if the Reporting Person's employment is terminated by the Issuer for cause or by the Reporting Person without good reason.
F2 Represents the number of shares withheld by the Issuer to cover tax withholding in connection with the settlement of PSUs on December 17, 2025.
F3 Represents the number of shares withheld by the Issuer to cover tax withholding in connection with the settlement of restricted stock units on December 17, 2025.