# EDGAR Filing Document

**Accession Number:** 0001107414
**File Stem:** 0001145549-25-045997
**Filing Date:** 2025-7
**Character Count:** 13101
**Document Hash:** 126444a01c01b89782a6bea7a8d0f9e3
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001145549-25-045997.hdr.sgml**: 20250708

**ACCESSION NUMBER**: 0001145549-25-045997

**CONFORMED SUBMISSION TYPE**: N-MFP3

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250630

**FILED AS OF DATE**: 20250708

**DATE AS OF CHANGE**: 20250708

**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:** 251109981

**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):** 2025-06-30

**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:** $8569236691.57

- **Amortized Cost of Portfolio Securities:** $8569236691.57

- **Cash:** $0.00

- **Total Other Assets:** $0.00

- **Total Liabilities:** $25541954.58

- **Net Assets of Series:** $8543694736.99

- **Number of Shares Outstanding (Series):** 8543767894.8700

- **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 (%)   |
|:---|:---|:---|:---|:---|
| 2025-06-02 | $61502987282.27           | $61702987282.27            | 96.7600%                  | 97.0700%                   |
| 2025-06-03 | $65947610467.29           | $66397610467.29            | 96.6100%                  | 97.2700%                   |
| 2025-06-04 | $63576859178.55           | $64026859178.55            | 96.4900%                  | 97.1700%                   |
| 2025-06-05 | $62608208066.71           | $62883208066.71            | 97.1100%                  | 97.5400%                   |
| 2025-06-06 | $57645326819.49           | $57920326819.49            | 96.8500%                  | 97.3200%                   |
| 2025-06-09 | $58111338118.22           | $58386338118.22            | 96.8900%                  | 97.3400%                   |
| 2025-06-10 | $57306100767.88           | $57581100767.88            | 96.8400%                  | 97.3100%                   |
| 2025-06-11 | $58989362605.53           | $58989362605.53            | 97.3700%                  | 97.3700%                   |
| 2025-06-12 | $57737324846.14           | $57737324846.14            | 97.3200%                  | 97.3200%                   |
| 2025-06-13 | $56738024740.40           | $56738024740.40            | 97.2500%                  | 97.2500%                   |
| 2025-06-16 | $58015624160.34           | $58015624160.34            | 97.3200%                  | 97.3200%                   |
| 2025-06-17 | $60944165342.49           | $60944165342.49            | 97.4400%                  | 97.4400%                   |
| 2025-06-18 | $63101361712.10           | $63101361712.10            | 97.5200%                  | 97.5200%                   |
| 2025-06-20 | $58677468799.77           | $58996644833.51            | 97.0100%                  | 97.5300%                   |
| 2025-06-23 | $61543904396.78           | $61543904396.78            | 97.4600%                  | 97.4600%                   |
| 2025-06-24 | $61230598390.01           | $61230598390.01            | 97.4400%                  | 97.4400%                   |
| 2025-06-25 | $60649716003.33           | $60649716003.33            | 97.4200%                  | 97.4200%                   |
| 2025-06-26 | $59275629932.24           | $59275629932.24            | 97.3600%                  | 97.3600%                   |
| 2025-06-27 | $57423108111.59           | $57423108111.59            | 97.2600%                  | 97.2600%                   |
| 2025-06-30 | $60289173052.27           | $60289173052.27            | 97.4000%                  | 97.4000%                   |

### 7-Day Gross Yield
| Date       | 7-Day Gross Yield   |
|:---|:---|
| 2025-06-02 | 4.3700%             |
| 2025-06-03 | 4.3700%             |
| 2025-06-04 | 4.3600%             |
| 2025-06-05 | 4.3600%             |
| 2025-06-06 | 4.3400%             |
| 2025-06-09 | 4.3300%             |
| 2025-06-10 | 4.3300%             |
| 2025-06-11 | 4.3300%             |
| 2025-06-12 | 4.3300%             |
| 2025-06-13 | 4.3300%             |
| 2025-06-16 | 4.3300%             |
| 2025-06-17 | 4.3400%             |
| 2025-06-18 | 4.3300%             |
| 2025-06-20 | 4.3300%             |
| 2025-06-23 | 4.3300%             |
| 2025-06-24 | 4.3300%             |
| 2025-06-25 | 4.3400%             |
| 2025-06-26 | 4.3400%             |
| 2025-06-27 | 4.3600%             |
| 2025-06-30 | 4.3600%             |

### Daily Net Asset Value per Share (Series)
| Date       | Net Asset Value per Share   |
|:---|:---|
| 2025-06-02 | 1.0000                      |
|  |  |
| 2025-06-03 | 1.0000                      |
|  |  |
| 2025-06-04 | 1.0000                      |
|  |  |
| 2025-06-05 | 1.0000                      |
|  |  |
| 2025-06-06 | 1.0000                      |
|  |  |
| 2025-06-09 | 1.0000                      |
|  |  |
| 2025-06-10 | 1.0000                      |
|  |  |
| 2025-06-11 | 1.0000                      |
|  |  |
| 2025-06-12 | 1.0000                      |
|  |  |
| 2025-06-13 | 1.0000                      |
|  |  |
| 2025-06-16 | 1.0000                      |
|  |  |
| 2025-06-17 | 1.0000                      |
|  |  |
| 2025-06-18 | 1.0000                      |
|  |  |
| 2025-06-20 | 1.0000                      |
|  |  |
| 2025-06-23 | 1.0000                      |
|  |  |
| 2025-06-24 | 1.0001                      |
|  |  |
| 2025-06-25 | 1.0000                      |
|  |  |
| 2025-06-26 | 1.0000                      |
|  |  |
| 2025-06-27 | 1.0000                      |
|  |  |
| 2025-06-30 | 1.0000                      |
|  |  |

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

### Class: A

- **Minimum Initial Investment:** $1000000000.00

- **Net Assets of Class:** $8543694736.99

- **Number of Shares Outstanding:** 8543767894.8700

- **Expense Reimbursement/Waiver:** 171639.00

**Daily Net Asset Value per Share (Class)**
| Date       | NAV per Share   |
|:---|:---|
| 2025-06-02 | 1.0000          |
|  |  |
| 2025-06-03 | 1.0000          |
|  |  |
| 2025-06-04 | 1.0000          |
|  |  |
| 2025-06-05 | 1.0000          |
|  |  |
| 2025-06-06 | 1.0000          |
|  |  |
| 2025-06-09 | 1.0000          |
|  |  |
| 2025-06-10 | 1.0000          |
|  |  |
| 2025-06-11 | 1.0000          |
|  |  |
| 2025-06-12 | 1.0000          |
|  |  |
| 2025-06-13 | 1.0000          |
|  |  |
| 2025-06-16 | 1.0000          |
|  |  |
| 2025-06-17 | 1.0000          |
|  |  |
| 2025-06-18 | 1.0000          |
|  |  |
| 2025-06-20 | 1.0000          |
|  |  |
| 2025-06-23 | 1.0000          |
|  |  |
| 2025-06-24 | 1.0001          |
|  |  |
| 2025-06-25 | 1.0000          |
|  |  |
| 2025-06-26 | 1.0000          |
|  |  |
| 2025-06-27 | 1.0000          |
|  |  |
| 2025-06-30 | 1.0000          |
|  |  |

**Daily Shareholder Flows**
| Date       | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| 2025-06-02 | $36559649.38              | $18279567.19            |
| 2025-06-03 | $20.22                    | $0.00                   |
| 2025-06-04 | $0.00                     | $4.42                   |
| 2025-06-05 | $1272627276.00            | $89940199.00            |
| 2025-06-06 | $0.00                     | $12377438.00            |
| 2025-06-09 | $0.00                     | $0.00                   |
| 2025-06-10 | $0.00                     | $0.00                   |
| 2025-06-11 | $1454740944.00            | $26873853.00            |
| 2025-06-12 | $0.00                     | $5313146.00             |
| 2025-06-13 | $0.00                     | $1227981.00             |
| 2025-06-16 | $0.00                     | $0.00                   |
| 2025-06-17 | $1371026408.00            | $49413194.00            |
| 2025-06-18 | $0.00                     | $2462418.00             |
| 2025-06-20 | $0.00                     | $0.00                   |
| 2025-06-23 | $0.00                     | $0.00                   |
| 2025-06-24 | $1693048571.00            | $75842399.00            |
| 2025-06-25 | $301000000.00             | $10620759.00            |
| 2025-06-26 | $0.00                     | $31952224.00            |
| 2025-06-27 | $155106885.00             | $1902565977.00          |
| 2025-06-30 | $75000000.00              | $0.00                   |

**Total Gross Subscriptions (Month):** $6359109753.60

**Total Gross Redemptions (Month):** $2226869159.61

**7-Day Net Yield (Class)**
| Date       | 7-Day Net Yield   |
|:---|:---|
| 2025-06-02 | 4.2900%           |
| 2025-06-03 | 4.2900%           |
| 2025-06-04 | 4.2800%           |
| 2025-06-05 | 4.2800%           |
| 2025-06-06 | 4.2600%           |
| 2025-06-09 | 4.2500%           |
| 2025-06-10 | 4.2500%           |
| 2025-06-11 | 4.2500%           |
| 2025-06-12 | 4.2500%           |
| 2025-06-13 | 4.2500%           |
| 2025-06-16 | 4.2500%           |
| 2025-06-17 | 4.2600%           |
| 2025-06-18 | 4.2500%           |
| 2025-06-20 | 4.2500%           |
| 2025-06-23 | 4.2500%           |
| 2025-06-24 | 4.2500%           |
| 2025-06-25 | 4.2500%           |
| 2025-06-26 | 4.2600%           |
| 2025-06-27 | 4.2700%           |
| 2025-06-30 | 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):** $8569236691.57
- **C.18.a - Value (excl. sponsor support):** $8569236691.57
- **C.19 - Percentage of Net Assets:** 100.0000%
- **C.17 - Yield as of Reporting Date:** 0.0000%
- **C.11 - Maturity Date (WAM):** 2025-07-01
- **C.12 - Maturity Date (WAL):** 2025-07-01
- **C.13 - Final Legal Maturity Date:** 2025-07-01
- **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:** 2025-07-08

**By:** /s/ Chad Hallett

**Name of Signing Officer:** Chad Hallett

**Title of Signing Officer:** Deputy Treasurer