# EDGAR Filing Document

**Accession Number:** 0001107414
**File Stem:** 0001145549-25-050736
**Filing Date:** 2025-8
**Character Count:** 13829
**Document Hash:** 55b2ba35b83c655bff8309d2d1eb4727
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001145549-25-050736.hdr.sgml**: 20250807

**ACCESSION NUMBER**: 0001145549-25-050736

**CONFORMED SUBMISSION TYPE**: N-MFP3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250731

**FILED AS OF DATE**: 20250807

**DATE AS OF CHANGE**: 20250807

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** STATE STREET INSTITUTIONAL INVESTMENT TRUST
- **CENTRAL INDEX KEY:** 0001107414

**ORGANIZATION NAME:**
- **EIN:** 046910804
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** N-MFP3
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-09819
- **FILM NUMBER:** 251192256

**BUSINESS ADDRESS:**
- **STREET 1:** ONE IRON STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210
- **BUSINESS PHONE:** 6176643920

**MAIL ADDRESS:**
- **STREET 1:** ONE IRON STREET
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210

## Series and Classes Contracts Data

### State Street Treasury Obligations Money Market Fund (Series ID: S000058519)

| Class ID   | Class Name                                          | Ticker Symbol   |
|:---|:---|:---|
| C000192374 | State Street Treasury Obligations Money Market Fund | TAQXX           |

# Form N-MFP3: Monthly Schedule of Portfolio Holdings

## N-MFP: Filer Information
**Submission Type:** N-MFP3
**CIK:** 0001107414

### General Information

**Report for (YYYY-MM-DD):** 2025-07-31

**Registrant Full Name:** STATE STREET INSTITUTIONAL INVESTMENT TRUST

**CIK Number of Registrant:** 0001107414

**LEI of Registrant:** 549300P1E098W6ES7M39

**Name of Series:** State Street Treasury Obligations Money Market Fund

**LEI of Series:** 549300Q6TZ3O71NFFG47

**EDGAR Series Identifier:** S000058519

**Total number of share classes in the series:** 1

**Is this the fund's final filing on Form N-MFP?:** No

**Has the fund acquired or merged with another fund?:** No

## Part A: Series-Level Information about the Fund

### Service Providers
| Role                          | Details                                         | File/CIK Number   |
|:---|:---|:---|
| Investment Adviser            | SSGA Funds Management, Inc.                     | 801-60103         |
| Independent Public Accountant | Ernst & Young  LLP<br>City: Boston<br>State: MA |  |
| Administrator                 | SSGA Funds Management, Inc.                     |  |
| Transfer Agent                | SS&C GIDS, Inc.<br>CIK: 0000027048              | 084-00448         |

### Fund Characteristics & Assets

- **Securities Act File Number:** 333-30810

- **Is this a Feeder Fund?:** Yes

- **Is this a Master Fund?:** No

- **Is this series for insurance company separate accounts?:** No

- **Money Market Fund Category:** Government

- **Is this a Retail Money Market Fund?:** No

- **Is this a Government Money Market Fund?:** No

- **WAM:** 1 days

- **WAL:** 1 days

- **Total Value of Portfolio Securities:** $3731703320.61

- **Amortized Cost of Portfolio Securities:** $3731703320.61

- **Cash:** $0.00

- **Total Other Assets:** $0.00

- **Total Liabilities:** $23132329.59

- **Net Assets of Series:** $3708570991.02

- **Number of Shares Outstanding (Series):** 3708644149.0300

- **Does the fund seek to maintain a stable price per share?:** Yes

- **Stable Price Per Share:** $1.00

- **Is cash management vehicle an affiliated fund?:** No

- **Does the fund apply liquidity fees?:** No

### Daily & Weekly Liquid Assets
| Date       | Daily Liquid Assets ($)   | Weekly Liquid Assets ($)   | Daily Liquid Assets (%)   | Weekly Liquid Assets (%)   |
|:---|:---|:---|:---|:---|
| 2025-07-01 | $63567394531.99           | $63567394531.99            | 97.5300%                  | 97.5300%                   |
| 2025-07-02 | $70532326014.58           | $70532326014.58            | 97.7600%                  | 97.7600%                   |
| 2025-07-03 | $63262676024.34           | $63262676024.34            | 97.4800%                  | 97.4800%                   |
| 2025-07-07 | $59046791773.94           | $59046791773.94            | 97.3200%                  | 97.3200%                   |
| 2025-07-08 | $58833276213.97           | $58833276213.97            | 97.3200%                  | 97.3200%                   |
| 2025-07-09 | $58677988625.17           | $58677988625.17            | 97.3100%                  | 97.3100%                   |
| 2025-07-10 | $58692596010.00           | $58892596010.00            | 97.3100%                  | 97.6400%                   |
| 2025-07-11 | $58480211937.02           | $58680211937.02            | 97.2800%                  | 97.6200%                   |
| 2025-07-14 | $58220840821.59           | $58420840821.59            | 97.2800%                  | 97.6100%                   |
| 2025-07-15 | $57925760046.98           | $58125760046.98            | 97.2600%                  | 97.6000%                   |
| 2025-07-16 | $59572999592.44           | $59692999592.44            | 97.6600%                  | 97.8500%                   |
| 2025-07-17 | $58584378852.82           | $58834378852.82            | 97.3000%                  | 97.7100%                   |
| 2025-07-18 | $57816543379.98           | $58066543379.98            | 97.2500%                  | 97.6700%                   |
| 2025-07-21 | $59052408100.24           | $59302408100.24            | 97.3100%                  | 97.7200%                   |
| 2025-07-22 | $57954010076.60           | $58204010076.60            | 97.2600%                  | 97.6800%                   |
| 2025-07-23 | $57370788768.99           | $57620788768.99            | 97.6400%                  | 98.0700%                   |
| 2025-07-24 | $55209759976.82           | $55459759976.82            | 97.1300%                  | 97.5700%                   |
| 2025-07-25 | $55048769530.95           | $55298769530.95            | 97.1000%                  | 97.5500%                   |
| 2025-07-28 | $55689686644.40           | $55939686644.40            | 97.1400%                  | 97.5800%                   |
| 2025-07-29 | $54965330107.57           | $54965330107.57            | 97.5400%                  | 97.5400%                   |
| 2025-07-30 | $54090637453.06           | $54090637453.06            | 97.0600%                  | 97.0600%                   |
| 2025-07-31 | $53382866221.27           | $53382866221.27            | 97.1700%                  | 97.1700%                   |

### 7-Day Gross Yield
| Date       | 7-Day Gross Yield   |
|:---|:---|
| 2025-07-01 | 4.3700%             |
| 2025-07-02 | 4.3700%             |
| 2025-07-03 | 4.3600%             |
| 2025-07-07 | 4.3500%             |
| 2025-07-08 | 4.3500%             |
| 2025-07-09 | 4.3400%             |
| 2025-07-10 | 4.3400%             |
| 2025-07-11 | 4.3400%             |
| 2025-07-14 | 4.3400%             |
| 2025-07-15 | 4.3400%             |
| 2025-07-16 | 4.3400%             |
| 2025-07-17 | 4.3400%             |
| 2025-07-18 | 4.3400%             |
| 2025-07-21 | 4.3400%             |
| 2025-07-22 | 4.3300%             |
| 2025-07-23 | 4.3300%             |
| 2025-07-24 | 4.3300%             |
| 2025-07-25 | 4.3400%             |
| 2025-07-28 | 4.3500%             |
| 2025-07-29 | 4.3500%             |
| 2025-07-30 | 4.3500%             |
| 2025-07-31 | 4.3600%             |

### Daily Net Asset Value per Share (Series)
| Date       | Net Asset Value per Share   |
|:---|:---|
| 2025-07-01 | 1.0000                      |
|  |  |
| 2025-07-02 | 1.0000                      |
|  |  |
| 2025-07-03 | 0.9999                      |
|  |  |
| 2025-07-07 | 0.9999                      |
|  |  |
| 2025-07-08 | 1.0000                      |
|  |  |
| 2025-07-09 | 1.0000                      |
|  |  |
| 2025-07-10 | 1.0000                      |
|  |  |
| 2025-07-11 | 1.0000                      |
|  |  |
| 2025-07-14 | 1.0000                      |
|  |  |
| 2025-07-15 | 1.0000                      |
|  |  |
| 2025-07-16 | 1.0000                      |
|  |  |
| 2025-07-17 | 1.0000                      |
|  |  |
| 2025-07-18 | 1.0000                      |
|  |  |
| 2025-07-21 | 1.0000                      |
|  |  |
| 2025-07-22 | 1.0000                      |
|  |  |
| 2025-07-23 | 0.9999                      |
|  |  |
| 2025-07-24 | 1.0000                      |
|  |  |
| 2025-07-25 | 1.0000                      |
|  |  |
| 2025-07-28 | 1.0000                      |
|  |  |
| 2025-07-29 | 1.0000                      |
|  |  |
| 2025-07-30 | 1.0000                      |
|  |  |
| 2025-07-31 | 1.0000                      |
|  |  |

## Part B: Class-Level Information about the Fund

### Class: A

- **Minimum Initial Investment:** $1000000000.00

- **Net Assets of Class:** $3708570991.02

- **Number of Shares Outstanding:** 3708644149.0300

- **Expense Reimbursement/Waiver:** 156527.00

**Daily Net Asset Value per Share (Class)**
| Date       | NAV per Share   |
|:---|:---|
| 2025-07-01 | 1.0000          |
|  |  |
| 2025-07-02 | 1.0000          |
|  |  |
| 2025-07-03 | 0.9999          |
|  |  |
| 2025-07-07 | 0.9999          |
|  |  |
| 2025-07-08 | 1.0000          |
|  |  |
| 2025-07-09 | 1.0000          |
|  |  |
| 2025-07-10 | 1.0000          |
|  |  |
| 2025-07-11 | 1.0000          |
|  |  |
| 2025-07-14 | 1.0000          |
|  |  |
| 2025-07-15 | 1.0000          |
|  |  |
| 2025-07-16 | 1.0000          |
|  |  |
| 2025-07-17 | 1.0000          |
|  |  |
| 2025-07-18 | 1.0000          |
|  |  |
| 2025-07-21 | 1.0000          |
|  |  |
| 2025-07-22 | 1.0000          |
|  |  |
| 2025-07-23 | 0.9999          |
|  |  |
| 2025-07-24 | 1.0000          |
|  |  |
| 2025-07-25 | 1.0000          |
|  |  |
| 2025-07-28 | 1.0000          |
|  |  |
| 2025-07-29 | 1.0000          |
|  |  |
| 2025-07-30 | 1.0000          |
|  |  |
| 2025-07-31 | 1.0000          |
|  |  |

**Daily Shareholder Flows**
| Date       | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| 2025-07-01 | $25449049.03              | $35246402.95            |
| 2025-07-02 | $12355013.71              | $1039231972.52          |
| 2025-07-03 | $0.00                     | $3559284.00             |
| 2025-07-07 | $0.00                     | $0.00                   |
| 2025-07-08 | $0.00                     | $1.00                   |
| 2025-07-09 | $0.00                     | $2150.63                |
| 2025-07-10 | $518246683.00             | $197277470.00           |
| 2025-07-11 | $0.00                     | $56031629.00            |
| 2025-07-14 | $0.00                     | $0.00                   |
| 2025-07-15 | $16875537.00              | $1232978083.00          |
| 2025-07-16 | $0.00                     | $2000003.00             |
| 2025-07-17 | $0.00                     | $33862644.00            |
| 2025-07-18 | $2.00                     | $520000000.00           |
| 2025-07-21 | $0.00                     | $0.00                   |
| 2025-07-22 | $0.00                     | $35892659.00            |
| 2025-07-23 | $173442109.00             | $1637197176.00          |
| 2025-07-24 | $2.00                     | $0.00                   |
| 2025-07-25 | $0.00                     | $2.00                   |
| 2025-07-28 | $3.00                     | $0.00                   |
| 2025-07-29 | $441176956.00             | $681680149.00           |
| 2025-07-30 | $0.00                     | $539709474.48           |
| 2025-07-31 | $0.00                     | $8000000.00             |

**Total Gross Subscriptions (Month):** $1187545354.74

**Total Gross Redemptions (Month):** $6022669100.58

**7-Day Net Yield (Class)**
| Date       | 7-Day Net Yield   |
|:---|:---|
| 2025-07-01 | 4.2900%           |
| 2025-07-02 | 4.2900%           |
| 2025-07-03 | 4.2800%           |
| 2025-07-07 | 4.2700%           |
| 2025-07-08 | 4.2700%           |
| 2025-07-09 | 4.2600%           |
| 2025-07-10 | 4.2600%           |
| 2025-07-11 | 4.2600%           |
| 2025-07-14 | 4.2600%           |
| 2025-07-15 | 4.2600%           |
| 2025-07-16 | 4.2600%           |
| 2025-07-17 | 4.2600%           |
| 2025-07-18 | 4.2600%           |
| 2025-07-21 | 4.2600%           |
| 2025-07-22 | 4.2500%           |
| 2025-07-23 | 4.2500%           |
| 2025-07-24 | 4.2500%           |
| 2025-07-25 | 4.2600%           |
| 2025-07-28 | 4.2700%           |
| 2025-07-29 | 4.2700%           |
| 2025-07-30 | 4.2700%           |
| 2025-07-31 | 4.2800%           |

**Beneficial/Record Owner Categories**
| Category                  | Other Category   | Record Owner %   | Beneficial Owner %   |
|:---|:---|:---|:---|
| Non-financial corporation |  | 99.9900%         | 0.0000%              |

## Part C: Schedule of Portfolio Securities

### Security 1: State Street Treasury Plus Money Market Portfolio

- **C.1 - Title:** State Street Treasury Plus Money Market Portfolio
- **C.6 - Investment Category:** Investment Company
- **Identifiers:** C.3 - CUSIP: FSSgAK183, C.3 - LEI: N/A, C.5 - Other ID: FSSgAK183
- **C.18 - Value (incl. sponsor support):** $3731703320.61
- **C.18.a - Value (excl. sponsor support):** $3731703320.61
- **C.19 - Percentage of Net Assets:** 100.0000%
- **C.17 - Yield as of Reporting Date:** 0.0000%
- **C.11 - Maturity Date (WAM):** 2025-08-01
- **C.12 - Maturity Date (WAL):** 2025-08-01
- **C.13 - Final Legal Maturity Date:** 2025-08-01
- **Characteristics:** C.9 Eligible Security? Yes, C.14 Has Demand Feature? No, C.15 Has Guarantee? No, C.16 Has Enhancement? No, C.22 Is an Illiquid Security? No, C.20 Is a Daily Liquid Asset? Yes, C.21 Is a Weekly Liquid Asset? Yes, C.23 Categorized at Level 3? No

## N-MFP: Signatures

**Registrant:** STATE STREET INSTITUTIONAL INVESTMENT TRUST

**Date:** 2025-08-07

**By:** /s/ Chad Hallett

**Name of Signing Officer:** Chad Hallett

**Title of Signing Officer:** Deputy Treasurer