X0306 4 2021-09-29 0 0001650648 4D Molecular Therapeutics Inc. FDMT 0001692929 SCHAFFER DAVID C/O 4D MOLECULAR THERAPEUTICS INC. 5858 HORTON STREET #455 EMERYVILLE CA 94608 1 0 0 0 Common Stock 2021-09-29 4 S 0 7806 27.9928 D 958950 D Common Stock 2021-09-29 4 S 0 8365 29.0565 D 950585 D Common Stock 2021-09-29 4 S 0 700 30.0631 D 949885 D Common Stock 2021-09-30 4 S 0 7836 26.6928 D 942049 D Common Stock 2021-09-30 4 S 0 4549 27.2774 D 937500 D Transaction made pursuant to a 10b5-1 trading plan adopted by the Reporting Person. The transaction was executed in multiple trades in prices ranging from $27.70 to $28.70, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The reporting person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. The transaction was executed in multiple trades in prices ranging from $28.71 to $29.69, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The reporting person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. The transaction was executed in multiple trades in prices ranging from $29.75 to $30.66, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The reporting person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. The transaction was executed in multiple trades in prices ranging from $26.07 to $27.06, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The reporting person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. The transaction was executed in multiple trades in prices ranging from $27.08 to $27.83, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The reporting person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. /s/ August J. Moretti, Attorney-in-Fact for David Schaffer 2021-10-01