# EDGAR Filing Document

**Accession Number:** 0000798244
**File Stem:** 0001145549-23-000628
**Filing Date:** 2023-1
**Character Count:** 26200
**Document Hash:** 86d4c754d001cf8d43e8e21ff7f36d59
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001145549-23-000628.hdr.sgml**: 20230109

**ACCESSION NUMBER**: 0001145549-23-000628

**CONFORMED SUBMISSION TYPE**: N-MFP2

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20221231

**FILED AS OF DATE**: 20230109

**DATE AS OF CHANGE**: 20230109

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MFS SERIES TRUST I
- **CENTRAL INDEX KEY:** 0000798244
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 1130

**FILING VALUES:**
- **FORM TYPE:** N-MFP2
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-04777
- **FILM NUMBER:** 23517771

**BUSINESS ADDRESS:**
- **STREET 1:** 111 HUNTINGTON AVENUE
- **STREET 2:** 21ST FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02199
- **BUSINESS PHONE:** 18006372929

**MAIL ADDRESS:**
- **STREET 1:** 111 HUNTINGTON AVENUE
- **STREET 2:** 21ST FLOOR
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02199

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MFS SERIES TRUST I /MA/
- **DATE OF NAME CHANGE:** 19940427

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MFS LIFETIME MANAGED SECTORS FUND
- **DATE OF NAME CHANGE:** 19930408

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** LIFETIME MANAGED SECTORS TRUST
- **DATE OF NAME CHANGE:** 19920703

## Series and Classes Contracts Data

### MFS U.S. Government Cash Reserve Fund (Series ID: S000000762)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000002179 | A            | MSRXX           |
| C000002182 | B            | MCRXX           |
| C000002183 | C            | MCCXX           |
| C000002184 | R1           | CRVXX           |
| C000002186 | R2           | CRMXX           |
| C000002187 | R3           | CRJXX           |
| C000002188 | R4           | CRKXX           |
| C000206004 | R6           | CRRXX           |
| C000206005 | I            | CRHXX           |

# Form N-MFP: Monthly Schedule of Portfolio Holdings

## N-MFP: Filer Information

**Submission Type:** N-MFP2

**Live/Test Flag:** —

**Is Electronic Copy of Paper Format:** —

**CIK:** —

### General Information

**Report for (YYYY-MM-DD):** 2022-12-31

**EDGAR Series Identifier:** S000000762

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

**Is this the fund's final filing on Form N-MFP?:** —

**Is Fund Liquidating?:** —

**Is Fund Merging/Being Acquired?:** —

**Has the fund acquired or merged with another fund during the reporting period?:** —

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

### Service Providers
| Item   | Role                          | Details                                            | File/CIK Number   |
|:---|:---|:---|:---|
| A.5    | Administrator                 | Massachusetts Financial Services Company           |  |
| A.4    | Independent Public Accountant | Deloitte & Touche LLP<br>City: Boston<br>State: MA |  |
| A.6    | Transfer Agent                | MFS Service Center, Inc<br>CIK: 0000769188         | 084-01316         |

### Fund Characteristics & Assets

- **A.1 - Securities Act File Number:** 033-07638

- **A.7 - Is this a Feeder Fund?:** No

- **A.8 - Is this a Master Fund?:** No

- **A.9 - Is this series primarily used to fund insurance company separate accounts?:** No

- **A.10 - Money Market Fund Category:** Exempt Government

- **A.11 - WAM:** 13 days

- **A.12 - WAL:** 13 days

- **Total Value of Portfolio Securities:** $516261181.99

- **Amortized Cost of Portfolio Securities:** $516185337.79

- **Cash:** $20.29

- **Total Other Assets:** $123345.21

- **Total Liabilities:** $3060414.76

- **Net Assets of Series:** $513248288.53

- **Number of Shares Outstanding (Series):** 513483096.53

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

- **7-Day Gross Yield:** 4.0400%

### Weekly Liquid Assets
| Period         | Daily Liquid Assets ($)   | Weekly Liquid Assets ($)   | Daily Liquid Assets (%)   | Weekly Liquid Assets (%)   |
|:---|:---|:---|:---|:---|
| Friday, Week 1 |  | $504546606.05              |  | 99.9000%                   |
| Friday, Week 2 |  | $503438507.99              |  | 99.9600%                   |
| Friday, Week 3 |  | $504611062.88              |  | 99.9800%                   |
| Friday, Week 4 |  | $504284470.49              |  | 99.9700%                   |
| Friday, Week 5 |  | $516185358.08              |  | 99.9600%                   |

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

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1000.00

- **B.3 - Net Assets of Class:** $194569464.45

- **B.4 - Shares Outstanding:** 194660036.60

- **B.7.7 - 7-Day Net Yield:** 3.6300%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class A during the period, MFS waived: $2,146 management fees; $20,483 expense limitation; MFD waived: $40,762 12b-1 fees.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $3056211.24               | $2002984.79             |
| Week 2   | $2086064.53               | $2652018.94             |
| Week 3   | $6201417.73               | $3840099.15             |
| Week 4   | $4652309.29               | $2952062.99             |
| Week 5   | $3322276.83               | $2531767.59             |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $17758426.29

- **Gross Redemptions for month:** $12643028.71

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1000.00

- **B.3 - Net Assets of Class:** $4704319.03

- **B.4 - Shares Outstanding:** 4706518.67

- **B.7.7 - 7-Day Net Yield:** 3.6300%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class B during the period, MFS waived: $54 management fees; $512 expense limitation; MFD waived: $4,081 12b-1 fees.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $20211.44                 | $29203.56               |
| Week 2   | $15371.15                 | $60164.48               |
| Week 3   | $1.78                     | $10005.21               |
| Week 4   | $91.09                    | $138060.94              |
| Week 5   | $0.00                     | $1806.22                |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $35675.46

- **Gross Redemptions for month:** $215647.27

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1000.00

- **B.3 - Net Assets of Class:** $33392084.42

- **B.4 - Shares Outstanding:** 33407684.65

- **B.7.7 - 7-Day Net Yield:** 3.6200%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class C during the period, MFS waived: $375 management fees; $3,575 expense limitation; MFD waived: $28,480 12b-1 fees.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $307029.74                | $100255.12              |
| Week 2   | $652758.61                | $243921.20              |
| Week 3   | $256523.32                | $387297.48              |
| Week 4   | $227136.83                | $563213.79              |
| Week 5   | $177860.10                | $162446.58              |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $1598425.32

- **Gross Redemptions for month:** $1392138.17

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1.00

- **B.3 - Net Assets of Class:** $9161729.33

- **B.4 - Shares Outstanding:** 9165983.36

- **B.7.7 - 7-Day Net Yield:** 3.6300%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class R1 during the period, MFS waived: $104 management fees; $989 expense limitation; MFD waived: $7,891 12b-1 fees.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $38456.83                 | $2282.63                |
| Week 2   | $9901.97                  | $492.58                 |
| Week 3   | $12537.84                 | $131.33                 |
| Week 4   | $29282.11                 | $338565.54              |
| Week 5   | $62055.89                 | $1811.74                |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $142898.67

- **Gross Redemptions for month:** $341036.19

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1.00

- **B.3 - Net Assets of Class:** $21467674.81

- **B.4 - Shares Outstanding:** 21477699.29

- **B.7.7 - 7-Day Net Yield:** 3.6300%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class R2 during the period, MFS waived: $246 management fees; $2,344 expense limitation; MFD waived: $9,351 12b-1 fees.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $124017.69                | $227951.48              |
| Week 2   | $65137.47                 | $1022.02                |
| Week 3   | $35981.71                 | $1464435.06             |
| Week 4   | $154235.23                | $80007.01               |
| Week 5   | $49510.44                 | $29192.26               |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $385850.20

- **Gross Redemptions for month:** $1775986.48

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1.00

- **B.3 - Net Assets of Class:** $17959157.68

- **B.4 - Shares Outstanding:** 17967731.22

- **B.7.7 - 7-Day Net Yield:** 3.6200%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class R3 during the period, MFS waived: $207 management fees; $1,970 expense limitation; MFD waived: $3,929 12b-1 fees.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $463481.80                | $210767.95              |
| Week 2   | $14986.40                 | $431838.02              |
| Week 3   | $14392.36                 | $3723.46                |
| Week 4   | $41122.99                 | $275120.41              |
| Week 5   | $54964.07                 | $438878.44              |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $556785.09

- **Gross Redemptions for month:** $1304642.05

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1.00

- **B.3 - Net Assets of Class:** $2700636.29

- **B.4 - Shares Outstanding:** 2701898.57

- **B.7.7 - 7-Day Net Yield:** 3.6300%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class R4 during the period, MFS waived: $30 management fees; $288 expense limitation.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $6717.36                  | $0.00                   |
| Week 4   | $0.00                     | $4.97                   |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $6712.39

- **Gross Redemptions for month:** $0.00

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1.00

- **B.3 - Net Assets of Class:** $212689644.87

- **B.4 - Shares Outstanding:** 212784205.73

- **B.7.7 - 7-Day Net Yield:** 3.6700%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class R6 during the period, MFS waived: $2,285 management fee; $21,774 expense limitation.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $585724.75                | $599239.22              |
| Week 2   | $351898.76                | $1072913.83             |
| Week 3   | $24030.89                 | $1141892.82             |
| Week 4   | $133928.61                | $1103237.31             |
| Week 5   | $11437150.61              | $1060294.46             |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $12469122.27

- **Gross Redemptions for month:** $4696173.79

### Class: Unknown Class (—)

- **B.2 - Minimum Initial Investment:** $1.00

- **B.3 - Net Assets of Class:** $16603577.65

- **B.4 - Shares Outstanding:** 16611338.44

- **B.7.7 - 7-Day Net Yield:** 3.6300%

- **Person Paying for Fund Expenses?:** Yes

- **Expense Reimbursement/Waiver Description:** For Class I during the period, MFS waived: $186 management fees; $1,769 expense limitation.

**Weekly Flows:**

| Period   | Gross Subscriptions ($)   | Gross Redemptions ($)   |
|:---|:---|:---|
| Week 1   | $40977.18                 | $8976.62                |
| Week 2   | $89771.30                 | $612267.85              |
| Week 3   | $85924.98                 | $10734.22               |
| Week 4   | $102548.27                | $67423.21               |
| Week 5   | $716.29                   | $1334.06                |

**Monthly Shareholder Flow Activity:**

- **Gross Subscriptions for month:** $319898.02

- **Gross Redemptions for month:** $700456.44

## Part C: Schedule of Portfolio Securities

### Security 1: BOFA Securities

- **C.1 - Title:** Bank of America NA 4.240000%
- **C.6 - Investment Category:** U.S. Treasury Repurchase Agreement, if collateralized only by U.S. Treasuries (including Strips) and cash
- **Identifiers:** C.3 - LEI: 549300HN4UKV1E2R3U73, CIK: 0001102113, C.5 - Other ID: 03199T002_4.24_0103
- **C.18 - Value (incl. sponsor support):** $85616000.00
- **C.18.a - Value (excl. sponsor support):** $85616000.00
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 16.6800%
- **C.17 - Yield as of Reporting Date:** 4.2400%
- **C.11 - Maturity Date (WAM):** 2023-01-03
- **C.12 - Maturity Date (WAL):** 2023-01-03
- **C.13 - Final Legal Maturity Date:** 2023-01-03
- **Characteristics:** 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

### Security 2: Federal Farm Credit Bank

- **C.1 - Title:** Federal Farm Credit Bank
- **C.6 - Investment Category:** U.S. Government Agency Debt
- **Identifiers:** C.3 - CUSIP: 313312BJ8, C.4 - ISIN: US313312BJ81
- **C.18 - Value (incl. sponsor support):** $29889682.80
- **C.18.a - Value (excl. sponsor support):** $29889682.80
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 5.8200%
- **C.17 - Yield as of Reporting Date:** 3.9200%
- **C.11 - Maturity Date (WAM):** 2023-02-02
- **C.12 - Maturity Date (WAL):** 2023-02-02
- **C.13 - Final Legal Maturity Date:** 2023-02-02
- **Characteristics:** 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? No, C.21 Is a Weekly Liquid Asset? Yes, C.23 Categorized at Level 3? No

### Security 3: Federal Home Loan Mortgage Corp.

- **C.1 - Title:** Federal Home Loan Mortgage Corp.
- **C.6 - Investment Category:** U.S. Government Agency Debt
- **Identifiers:** C.3 - CUSIP: 313396AD5, C.4 - ISIN: US313396AD53, C.3 - LEI: S6XOOCT0IEG5ABCC6L87
- **C.18 - Value (incl. sponsor support):** $29996436.00
- **C.18.a - Value (excl. sponsor support):** $29996436.00
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 5.8400%
- **C.17 - Yield as of Reporting Date:** 2.2300%
- **C.11 - Maturity Date (WAM):** 2023-01-04
- **C.12 - Maturity Date (WAL):** 2023-01-04
- **C.13 - Final Legal Maturity Date:** 2023-01-04
- **Characteristics:** 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? No, C.21 Is a Weekly Liquid Asset? Yes, C.23 Categorized at Level 3? No

### Security 4: Federal Home Loan Mortgage Corp.

- **C.1 - Title:** Federal Home Loan Mortgage Corp.
- **C.6 - Investment Category:** U.S. Government Agency Debt
- **Identifiers:** C.3 - CUSIP: 313396AF0, C.4 - ISIN: US313396AF02, C.3 - LEI: S6XOOCT0IEG5ABCC6L87
- **C.18 - Value (incl. sponsor support):** $16993941.71
- **C.18.a - Value (excl. sponsor support):** $16993941.71
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 3.3100%
- **C.17 - Yield as of Reporting Date:** 2.8000%
- **C.11 - Maturity Date (WAM):** 2023-01-06
- **C.12 - Maturity Date (WAL):** 2023-01-06
- **C.13 - Final Legal Maturity Date:** 2023-01-06
- **Characteristics:** 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? No, C.21 Is a Weekly Liquid Asset? Yes, C.23 Categorized at Level 3? No

### Security 5: Federal National Mortgage Assoc.

- **C.1 - Title:** Federal National Mortgage Assoc.
- **C.6 - Investment Category:** U.S. Government Agency Debt
- **Identifiers:** C.3 - CUSIP: 313588AD7, C.4 - ISIN: US313588AD77, C.3 - LEI: B1V7KEBTPIMZEU4LTD58
- **C.18 - Value (incl. sponsor support):** $15498158.60
- **C.18.a - Value (excl. sponsor support):** $15498158.60
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 3.0200%
- **C.17 - Yield as of Reporting Date:** 2.3500%
- **C.11 - Maturity Date (WAM):** 2023-01-04
- **C.12 - Maturity Date (WAL):** 2023-01-04
- **C.13 - Final Legal Maturity Date:** 2023-01-04
- **Characteristics:** 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? No, C.21 Is a Weekly Liquid Asset? Yes, C.23 Categorized at Level 3? No

### Security 6: Federal National Mortgage Assoc.

- **C.1 - Title:** Federal National Mortgage Assoc.
- **C.6 - Investment Category:** U.S. Government Agency Debt
- **Identifiers:** C.3 - CUSIP: 313588AT2, C.4 - ISIN: US313588AT20, C.3 - LEI: B1V7KEBTPIMZEU4LTD58
- **C.18 - Value (incl. sponsor support):** $31443911.73
- **C.18.a - Value (excl. sponsor support):** $31443911.73
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 6.1300%
- **C.17 - Yield as of Reporting Date:** 3.5100%
- **C.11 - Maturity Date (WAM):** 2023-01-18
- **C.12 - Maturity Date (WAL):** 2023-01-18
- **C.13 - Final Legal Maturity Date:** 2023-01-18
- **Characteristics:** 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? No, C.21 Is a Weekly Liquid Asset? Yes, C.23 Categorized at Level 3? No

### Security 7: JP Morgan Securities LLC

- **C.1 - Title:** JP Morgan Securities LLC 4.250000%
- **C.6 - Investment Category:** U.S. Treasury Repurchase Agreement, if collateralized only by U.S. Treasuries (including Strips) and cash
- **Identifiers:** C.3 - LEI: ZBUT11V806EZRVTWT807, CIK: 0001168163, C.5 - Other ID: 446199002_4.25_0103
- **C.18 - Value (incl. sponsor support):** $76666000.00
- **C.18.a - Value (excl. sponsor support):** $76666000.00
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 14.9400%
- **C.17 - Yield as of Reporting Date:** 4.2500%
- **C.11 - Maturity Date (WAM):** 2023-01-03
- **C.12 - Maturity Date (WAL):** 2023-01-03
- **C.13 - Final Legal Maturity Date:** 2023-01-03
- **Characteristics:** 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

### Security 8: U.S. Treasury Bill

- **C.1 - Title:** U.S. Treasury Bill
- **C.6 - Investment Category:** U.S. Treasury Debt
- **Identifiers:** C.3 - CUSIP: 912796S34, C.4 - ISIN: US912796S348, C.3 - LEI: 254900HROIFWPRGM1V77
- **C.18 - Value (incl. sponsor support):** $29426863.31
- **C.18.a - Value (excl. sponsor support):** $29426863.31
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 5.7300%
- **C.17 - Yield as of Reporting Date:** 3.5000%
- **C.11 - Maturity Date (WAM):** 2023-01-26
- **C.12 - Maturity Date (WAL):** 2023-01-26
- **C.13 - Final Legal Maturity Date:** 2023-01-26
- **Characteristics:** 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

### Security 9: U.S. Treasury Bill

- **C.1 - Title:** U.S. Treasury Bill
- **C.6 - Investment Category:** U.S. Treasury Debt
- **Identifiers:** C.3 - CUSIP: 912796X95, C.4 - ISIN: US912796X959, C.3 - LEI: 254900HROIFWPRGM1V77
- **C.18 - Value (incl. sponsor support):** $37992326.28
- **C.18.a - Value (excl. sponsor support):** $37992326.28
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 7.4000%
- **C.17 - Yield as of Reporting Date:** 2.4200%
- **C.11 - Maturity Date (WAM):** 2023-01-05
- **C.12 - Maturity Date (WAL):** 2023-01-05
- **C.13 - Final Legal Maturity Date:** 2023-01-05
- **Characteristics:** 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

### Security 10: U.S. Treasury Bill

- **C.1 - Title:** U.S. Treasury Bill
- **C.6 - Investment Category:** U.S. Treasury Debt
- **Identifiers:** C.3 - CUSIP: 912796XR5, C.4 - ISIN: US912796XR55, C.3 - LEI: 254900HROIFWPRGM1V77
- **C.18 - Value (incl. sponsor support):** $43961802.28
- **C.18.a - Value (excl. sponsor support):** $43961802.28
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 8.5700%
- **C.17 - Yield as of Reporting Date:** 3.2200%
- **C.11 - Maturity Date (WAM):** 2023-01-12
- **C.12 - Maturity Date (WAL):** 2023-01-12
- **C.13 - Final Legal Maturity Date:** 2023-01-12
- **Characteristics:** 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

### Security 11: U.S. Treasury Bill

- **C.1 - Title:** U.S. Treasury Bill
- **C.6 - Investment Category:** U.S. Treasury Debt
- **Identifiers:** C.3 - CUSIP: 912796XT1, C.4 - ISIN: US912796XT12, C.3 - LEI: 254900HROIFWPRGM1V77
- **C.18 - Value (incl. sponsor support):** $25419094.11
- **C.18.a - Value (excl. sponsor support):** $25419094.11
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 4.9500%
- **C.17 - Yield as of Reporting Date:** 3.7400%
- **C.11 - Maturity Date (WAM):** 2023-02-02
- **C.12 - Maturity Date (WAL):** 2023-02-02
- **C.13 - Final Legal Maturity Date:** 2023-02-02
- **Characteristics:** 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

### Security 12: U.S. Treasury Bill

- **C.1 - Title:** U.S. Treasury Bill
- **C.6 - Investment Category:** U.S. Treasury Debt
- **Identifiers:** C.3 - CUSIP: 912796ZJ1, C.4 - ISIN: US912796ZJ12, C.3 - LEI: 254900HROIFWPRGM1V77
- **C.18 - Value (incl. sponsor support):** $23983117.68
- **C.18.a - Value (excl. sponsor support):** $23983117.68
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 4.6700%
- **C.17 - Yield as of Reporting Date:** 3.2200%
- **C.11 - Maturity Date (WAM):** 2023-01-10
- **C.12 - Maturity Date (WAL):** 2023-01-10
- **C.13 - Final Legal Maturity Date:** 2023-01-10
- **Characteristics:** 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

### Security 13: U.S. Treasury Bill

- **C.1 - Title:** U.S. Treasury Bill
- **C.6 - Investment Category:** U.S. Treasury Debt
- **Identifiers:** C.3 - CUSIP: 912796ZK8, C.4 - ISIN: US912796ZK84, C.3 - LEI: 254900HROIFWPRGM1V77
- **C.18 - Value (incl. sponsor support):** $36447782.01
- **C.18.a - Value (excl. sponsor support):** $36447782.01
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 7.1000%
- **C.17 - Yield as of Reporting Date:** 3.5500%
- **C.11 - Maturity Date (WAM):** 2023-01-17
- **C.12 - Maturity Date (WAL):** 2023-01-17
- **C.13 - Final Legal Maturity Date:** 2023-01-17
- **Characteristics:** 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

### Security 14: U.S. Treasury Bill

- **C.1 - Title:** U.S. Treasury Bill
- **C.6 - Investment Category:** U.S. Treasury Debt
- **Identifiers:** C.3 - CUSIP: 912796ZL6, C.4 - ISIN: US912796ZL67, C.3 - LEI: 254900HROIFWPRGM1V77
- **C.18 - Value (incl. sponsor support):** $32926065.48
- **C.18.a - Value (excl. sponsor support):** $32926065.48
- **Principal Amount:** —
- **Amortized Cost:** —
- **Fair Value:** —
- **C.19 - Percentage of Net Assets:** 6.4200%
- **C.17 - Yield as of Reporting Date:** 3.6800%
- **C.11 - Maturity Date (WAM):** 2023-01-24
- **C.12 - Maturity Date (WAL):** 2023-01-24
- **C.13 - Final Legal Maturity Date:** 2023-01-24
- **Characteristics:** 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:** MFS Series Trust I

**Date:** 2023-01-09

**By:** Kino Clark

**Name of Signing Officer:** Kino Clark

**Title of Signing Officer:** Assistant Treasurer