144 0001805916 XXXXXXXX LIVE 0001556263 Syros Pharmaceuticals 001-37813 35 Cambridge Park Drive Cambridge MA 02140 6177441340 Flagship Pioneering Fund VII, L.P. Affiliate Common J.P. Morgan Securities LLC

390 Madison Avenue 6th Floor New York NY 10017

1135308 272473.92 26832457 12/27/2024 Nasdaq Common 09/15/2022 Private Investment in a Public Entity Issuer N 1135308 01/06/2025 Cashless Exercise of Warrant Shares N Flagship Pioneering Fund VII

35 CambridgePark Drive Cambridge MA 02140

Common 12/13/2024 1000000 203019 Flagship Pioneering Fund VII

35 CambridgePark Drive Cambridge MA 02140

Common 12/27/2024 1331624 262983 01/16/2025 /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Flagship Pioneering Fund VII, L.P.