NPORT-P false 0001107414 XXXXXXXX S000050331 C000158901 C000158902 C000158903 STATE STREET INSTITUTIONAL INVESTMENT TRUST 811-09819 0001107414 549300P1E098W6ES7M39 One Congress Street Boston 02114 (800) 647-7327 STATE STREET SMALL/MID CAP EQUITY INDEX FUND S000050331 54930090OO78X0U66F30 2026-12-31 2026-03-31 N 767464280.87 102369.02 767361911.85 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 0.00000000 N State Street Small/Mid Cap Equity Index Portfolio 54930001FXUIVS800B48 85749T707 2340757.86000000 NS USD 767464280.87000000 100.0133403832 Long EC RF US N 1 N N N 2026-04-30 STATE STREET INSTITUTIONAL INVESTMENT TRUST Arthur Jensen Arthur Jensen Deputy Treasurer XXXX