N-MFP3 0001107414 XXXXXXXX 2026-05-31 STATE STREET INSTITUTIONAL INVESTMENT TRUST 0001107414 549300P1E098W6ES7M39 State Street Treasury Obligations Money Market Fund 549300Q6TZ3O71NFFG47 S000058519 1 N N 333-30810 SSGA Funds Management, Inc. 801-60103 Ernst & Young LLP Boston MA SSGA Funds Management, Inc. SS&C GIDS, Inc. 0000027048 084-00448 Y 0001094885 Treasury Plus Money Market Portfolio S000019934 N N Government N N 1 1 76520796776.95 76620796776.95 0.9818 0.9831 2026-05-01 85233519081.72 85558519081.72 0.9812 0.9850 2026-05-04 86325564791.72 86650564791.72 0.9814 0.9851 2026-05-05 85201077499.43 85526077499.43 0.9812 0.9849 2026-05-06 72955915411.32 73760915411.32 0.9755 0.9863 2026-05-07 70183573450.39 70183573450.39 0.9815 0.9815 2026-05-08 71299733624.69 71299733624.69 0.9788 0.9788 2026-05-11 74015248114.77 74015248114.77 0.9796 0.9796 2026-05-12 71761379084.78 71761379084.78 0.9790 0.9790 2026-05-13 70591911977.69 70591911977.69 0.9786 0.9786 2026-05-14 70424992496.50 70424992496.50 0.9784 0.9784 2026-05-15 72334842526.88 72334842526.88 0.9790 0.9790 2026-05-18 72465368351.47 72465368351.47 0.9791 0.9791 2026-05-19 72269887039.35 72269887039.35 0.9790 0.9790 2026-05-20 71265356192.85 71265356192.85 0.9787 0.9787 2026-05-21 70028798614.57 70028798614.57 0.9780 0.9780 2026-05-22 70668486174.03 70668486174.03 0.9784 0.9784 2026-05-26 73762757121.93 73762757121.93 0.9792 0.9792 2026-05-27 73301847911.75 73301847911.75 0.9790 0.9790 2026-05-28 76773156744.97 76773156744.97 0.9798 0.9798 2026-05-29 0.00 3617374318.72 3617374318.72 0.00 11924955.36 3605449363.36 3605524110.0500 Y 1.0000 0.0370 2026-05-01 0.0369 2026-05-04 0.0369 2026-05-05 0.0369 2026-05-06 0.0368 2026-05-07 0.0368 2026-05-08 0.0367 2026-05-11 0.0367 2026-05-12 0.0367 2026-05-13 0.0367 2026-05-14 0.0366 2026-05-15 0.0366 2026-05-18 0.0366 2026-05-19 0.0365 2026-05-20 0.0365 2026-05-21 0.0364 2026-05-22 0.0365 2026-05-26 0.0366 2026-05-27 0.0367 2026-05-28 0.0368 2026-05-29 1.0000 2026-05-01 1.0000 2026-05-04 1.0000 2026-05-05 1.0000 2026-05-06 1.0000 2026-05-07 1.0000 2026-05-08 0.9999 2026-05-11 1.0000 2026-05-12 1.0000 2026-05-13 0.9999 2026-05-14 0.9999 2026-05-15 1.0000 2026-05-18 1.0000 2026-05-19 1.0000 2026-05-20 0.9999 2026-05-21 0.9999 2026-05-22 0.9999 2026-05-26 0.9999 2026-05-27 0.9999 2026-05-28 0.9999 2026-05-29 N N A C000192374 1000000000.00 3605449363.36 3605524110.0500 1.0000 2026-05-01 1.0000 2026-05-04 1.0000 2026-05-05 1.0000 2026-05-06 1.0000 2026-05-07 1.0000 2026-05-08 0.9999 2026-05-11 1.0000 2026-05-12 1.0000 2026-05-13 0.9999 2026-05-14 0.9999 2026-05-15 1.0000 2026-05-18 1.0000 2026-05-19 1.0000 2026-05-20 0.9999 2026-05-21 0.9999 2026-05-22 0.9999 2026-05-26 0.9999 2026-05-27 0.9999 2026-05-28 0.9999 2026-05-29 22457028.89 62983848.36 2026-05-01 12.92 0.00 2026-05-04 0.00 70594018.23 2026-05-05 0.00 707942.00 2026-05-06 0.00 0.00 2026-05-07 0.00 0.00 2026-05-08 0.00 0.00 2026-05-11 0.00 526590.00 2026-05-12 0.00 0.00 2026-05-13 0.00 0.00 2026-05-14 0.00 0.00 2026-05-15 0.00 0.00 2026-05-18 0.00 0.00 2026-05-19 0.00 0.00 2026-05-20 0.00 0.00 2026-05-21 0.00 100000000.00 2026-05-22 0.00 5759054.19 2026-05-26 0.00 0.00 2026-05-27 0.00 149392271.00 2026-05-28 0.00 68000000.00 2026-05-29 22457041.81 457963723.78 0.0362 2026-05-01 0.0361 2026-05-04 0.0361 2026-05-05 0.0361 2026-05-06 0.0360 2026-05-07 0.0360 2026-05-08 0.0359 2026-05-11 0.0359 2026-05-12 0.0359 2026-05-13 0.0359 2026-05-14 0.0358 2026-05-15 0.0358 2026-05-18 0.0358 2026-05-19 0.0357 2026-05-20 0.0357 2026-05-21 0.0356 2026-05-22 0.0357 2026-05-26 0.0358 2026-05-27 0.0359 2026-05-28 0.0360 2026-05-29 Y 113243.00 Non-financial corporation 0.9999 0.00 N State Street Treasury Plus Money Market Portfolio State Street Treasury Plus Money Market Portfolio FSSgAK183 5493008OWE0VKOXO4934 FSSgAK183 Investment Company Y 2026-06-01 2026-06-01 2026-06-01 N N N 0.0000 3617374318.72 3617374318.72 1.0000 N Y Y N STATE STREET INSTITUTIONAL INVESTMENT TRUST 2026-06-05 /s/ Chad Hallett Chad Hallett Deputy Treasurer