# EDGAR Filing Document

**Accession Number:** 0000742212
**File Stem:** 0001752724-23-058528
**Filing Date:** 2023-3
**Character Count:** 43487
**Document Hash:** 599c60d1c0a2c771e05064260df1d081
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001752724-23-058528.hdr.sgml**: 20230316

**ACCESSION NUMBER**: 0001752724-23-058528

**CONFORMED SUBMISSION TYPE**: NPORT-P/A

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20221231

**FILED AS OF DATE**: 20230316

**DATE AS OF CHANGE**: 20230316

**PERIOD START**: 20221231

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** NORTHWESTERN MUTUAL SERIES FUND INC
- **CENTRAL INDEX KEY:** 0000742212
- **IRS NUMBER:** 391603401
- **STATE OF INCORPORATION:** MD
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** NPORT-P/A
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-03990
- **FILM NUMBER:** 23737904

**BUSINESS ADDRESS:**
- **STREET 1:** 720 E WISCONSIN AVE
- **CITY:** MILWAUKEE
- **STATE:** WI
- **ZIP:** 53202
- **BUSINESS PHONE:** 4142992508

**MAIL ADDRESS:**
- **STREET 1:** 720 EAST WISCONSIN AVE
- **CITY:** MILWAUKEE
- **STATE:** WI
- **ZIP:** 53202

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** NORTHWESTERN MUTUAL VARIABLE LIFE SERIES FUND INC
- **DATE OF NAME CHANGE:** 19940830

## Series and Classes Contracts Data

### Long-Term US Government Bond Portfolio (Series ID: S000018234)

| Class ID   | Class Name                             | Ticker Symbol   |
|:---|:---|:---|
| C000050282 | Long-Term US Government Bond Portfolio |  |

## Form NPORT-P: Monthly Portfolio Investments Report

### NPORT-P: Part A: General Information

**Item A.1. Information about the Registrant.**

- **a. Name of Registrant:** NORTHWESTERN MUTUAL SERIES FUND INC

- **b. Investment Company Act file number:** 811-03990

- **c. CIK number of Registrant:** 0000742212

- **d. LEI of Registrant:** 549300T1UBX7MDSNZA55

- **e. Address and telephone number of Registrant.**

  - **Street Address 1:** 720 E WISCONSIN AVE

  - **City:** MILWAUKEE

  - **State:** WI

  - **Foreign country:** US

  - **Zip / Postal Code:** 53202

  - **Telephone number:** 414-271-1444

**Item A.2. Information about the Series.**

- **a. Name of Series:** Long-Term US Government Bond Portfolio

- **b. EDGAR series identifier (if any):** S000018234

- **c. LEI of Series:** G1NIKRLT4013DJUHQR28

**Item A.3. Reporting period.**

- **a. Date of fiscal year-end:** 2022-12-31

- **b. Date as of which information is reported:** 2022-12-31

**Item A.4. Final filing**

Does the Fund anticipate that this will be its final filing on Form N-PORT? **No**

### Fund Information

**Total Assets:** $253288171.53

**Total Liabilities:** $153156428.56

**Net Assets:** $100131742.97

**Delayed Delivery Securities:** $143013065.70

**Cash Not Reported:** $966267.21

**Currency Risk Metrics (dv01):**

- 

**Credit Spread Risk - Investment Grade (dv01):**

- **3-Month:** -28.72000000 | **1-Year:** -563.72000000 | **5-Year:** -1323.18000000 | **10-Year:** -36.54000000 | **30-Year:** -0.32000000

**Credit Spread Risk - Non-Investment Grade (dv01):**

- **3-Month:** -0.91000000 | **1-Year:** -15.22000000 | **5-Year:** -61.74000000 | **10-Year:** -683.19000000 | **30-Year:** -356.43000000

**Monthly Return Information**

| Class               | Month 1 Return (%)   | Month 2 Return (%)   | Month 3 Return (%)   |
|:---|:---|:---|:---|
| Class ID C000050282 | -5.33%               | 7.07%                | -2.40%               |

**Monthly Gains & Losses**

| Period   | Net Realized Gain/Loss   | Net Unrealized Appreciation/Depreciation   |
|:---|:---|:---|
| Month 1  | $-2470389.72             | $-3302646.90                               |
| Month 2  | $2754322.83              | $4353284.10                                |
| Month 3  | $2299783.47              | $-5649771.96                               |

**Designated Index Information**

- **Index Name:** Bloomberg Long-Term U.S. Treasury Index

- **Index Identifier:** LUTLTRUU

### Schedule of Portfolio Investments

| Name                                           | Title                                                                                                                  | Identifiers                                   | Payoff Profile   | Asset Category   | Issuer Category   | Country   |   Balance | Units   | Value (USD)   | % of Net Assets   | Maturity Date   | Coupon Type   | Annualized Rate (%)   | Restricted?   |   Fair Value Level | Lending Status   |
|:---|:---|:---|:---|:---|:---|:---|---:|:---|:---|:---|:---|:---|:---|:---|---:|:---|
| Merrill Lynch Mortgage Investors Trust         | Merrill Lynch Mortgage Investors Trust MLMI Series 2003-A4                                                             | CUSIP: 589929W87<br>LEI: 9DJT3UXIJIZJI4WXO774 | Long             | ABS-MBS          | CORP              | US        |       594 | PA      | $545.20       | 0.00%             | 2033-05-25      | Variable      | 2.97%                 | No            |                  2 | On Loan: No      |
| UMBS, TBA                                      | Uniform Mortgage-Backed Security, TBA                                                                                  | CUSIP: 01F040628<br>LEI: N/A                  | Long             | ABS-MBS          | USGSE             | US        |   1500000 | PA      | $1406607.11   | 1.40%             | 2053-02-15      | Fixed         | 4.00%                 | No            |                  2 | On Loan: No      |
| Government National Mortgage Association       | Government National Mortgage Association                                                                               | CUSIP: 38377GMM8<br>LEI: 549300M8ZYFG0OCMTT87 | Long             | ABS-MBS          | USGA              | US        |    197556 | PA      | $164046.28    | 0.16%             | 2035-09-20      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| ECMC Group Student Loan Trust                  | ECMC Group Student Loan Trust 2018-1                                                                                   | CUSIP: 26828HAA5<br>LEI: N/A                  | Long             | ABS-O            | CORP              | US        |     53518 | PA      | $50856.00     | 0.05%             | 2068-02-27      | Floating      | 5.14%                 | No            |                  2 | On Loan: No      |
| FHLMC STRUCTURED PASS THROUGH                  | Freddie Mac Structured Pass-Through Certificates                                                                       | CUSIP: 31395A3J2<br>LEI: 254900HROIFWPRGM1V77 | Long             | ABS-MBS          | USGSE             | US        |      4455 | PA      | $4459.42      | 0.00%             | 2044-07-25      | Floating      | 3.45%                 | No            |                  2 | On Loan: No      |
| Chicago Mercantile Exchange                    | Long: BWU01D5J2 IRS USD R V 12MSOFR SWUV1D5J4 CCPOIS / Short: BWU01D5J2 IRS USD P F  1.75000 SWU01D5J2 CCPOIS          | CUSIP: 000000000<br>LEI: SNZ2OJLFK8MNNCLQOF39 | N/A              | DIR              |  | US        |   1700000 | OU      | $426591.88    | 0.43%             |  |  |  | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Fannie Mae REMICS                                                                                                      | CUSIP: 3136A76U1<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |     26760 | PA      | $26082.36     | 0.03%             | 2042-09-25      | Floating      | 4.89%                 | No            |                  2 | On Loan: No      |
| VESSEL MANAGEMENT SERVIC                       | Vessel Management Services Inc                                                                                         | CUSIP: 228027AA6<br>LEI: 549300FGG4OD84UNFA43 | Long             | DBT              | CORP              | US        |    389000 | PA      | $349998.88    | 0.35%             | 2036-08-15      | Fixed         | 3.43%                 | No            |                  2 | On Loan: No      |
| Freddie Mac Military Housing Bonds Resec Trust | Freddie Mac Military Housing Bonds Resecuritization Trust Certificates 2015-R1                                         | CUSIP: 35563CAJ7<br>LEI: 549300ZG8WH0M4JSUM77 | Long             | ABS-MBS          | USGSE             | US        |    562136 | PA      | $528261.20    | 0.53%             | 2052-10-25      | Variable      | 4.32%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SW9<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1900000 | PA      | $1342914.07   | 1.34%             | 2041-02-15      | Fixed         | 1.88%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond - WI Reopening                                                                        | CUSIP: 912810TM0<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1000000 | PA      | $979062.50    | 0.98%             | 2042-11-15      | Fixed         | 4.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810TB4<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |  21760000 | PA      | $13781900.11  | 13.76%            | 2051-11-15      | Fixed         | 1.88%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810RK6<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1470000 | PA      | $1106691.79   | 1.11%             | 2045-02-15      | Fixed         | 2.50%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SL3<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |  12920000 | PA      | $8532751.59   | 8.52%             | 2050-02-15      | Fixed         | 2.00%                 | No            |                  2 | On Loan: No      |
| Hilton USA Trust                               | Hilton USA Trust 2016-HHV                                                                                              | CUSIP: 43300LAA8<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    600000 | PA      | $543142.98    | 0.54%             | 2038-11-05      | Fixed         | 3.72%                 | No            |                  2 | On Loan: No      |
| Chicago Board of Trade                         | US LONG BOND(CBT) MAR23                                                                                                | CUSIP: 000000000<br>LEI: 549300EX04Q2QBFQTQ27 | N/A              | DIR              |  | US        |       -89 | NC      | $-3602.99     | -0.00%            |  |  |  | No            |                  1 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SC3<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   2430000 | PA      | $2042244.15   | 2.04%             | 2048-05-15      | Fixed         | 3.13%                 | No            |                  2 | On Loan: No      |
| GS Mortgage Securities Trust                   | GS Mortgage Securities Trust 2015-590M                                                                                 | CUSIP: 36250WAG5<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    300000 | PA      | $266568.42    | 0.27%             | 2035-10-10      | Variable      | 3.81%                 | No            |                  2 | On Loan: No      |
| UMBS, TBA                                      | Uniform Mortgage-Backed Security, TBA                                                                                  | CUSIP: 01F040610<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |   1700000 | PA      | $1594021.90   | 1.59%             | 2053-01-15      | Fixed         | 4.00%                 | No            |                  2 | On Loan: No      |
| Freddie Mac                                    | Freddie Mac REMICS                                                                                                     | CUSIP: 3137BD4R4<br>LEI: S6XOOCT0IEG5ABCC6L87 | Long             | ABS-MBS          | USGSE             | US        |    621775 | PA      | $499490.17    | 0.50%             | 2053-04-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| Towd Point Mortgage Trust                      | Towd Point Mortgage Trust 2020-1                                                                                       | CUSIP: 89178WBB3<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    200000 | PA      | $167378.70    | 0.17%             | 2060-01-25      | Variable      | 3.10%                 | No            |                  2 | On Loan: No      |
| UMBS, TBA                                      | Uniform Mortgage-Backed Security, TBA                                                                                  | CUSIP: 01F042616<br>LEI: N/A                  | Short            | ABS-MBS          | USGSE             | US        |  -4600000 | PA      | $-4426378.93  | -4.42%            | 2053-01-15      | Fixed         | 4.50%                 | No            |                  2 | On Loan: No      |
| Chicago Board of Trade                         | US 10YR ULTRA FUT MAR23                                                                                                | CUSIP: 000000000<br>LEI: 549300EX04Q2QBFQTQ27 | N/A              | DIR              |  | US        |      -113 | NC      | $47563.83     | 0.05%             |  |  |  | No            |                  1 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SH2<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1350000 | PA      | $1086275.39   | 1.08%             | 2049-05-15      | Fixed         | 2.88%                 | No            |                  2 | On Loan: No      |
| CityLine Commercial Mortgage Trust             | CityLine Commercial Mortgage Trust 2016-CLNE                                                                           | CUSIP: 178772AA7<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    600000 | PA      | $577686.96    | 0.58%             | 2031-11-10      | Variable      | 2.78%                 | No            |                  2 | On Loan: No      |
| RFCSP STRIP PRINCIPAL                          | Resolution Funding Corp Principal Strip                                                                                | CUSIP: 76116FAC1<br>LEI: N/A                  | Long             | DBT              | USGA              | US        |   4800000 | PA      | $3482296.32   | 3.48%             | 2030-04-15      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| Extended Stay America Trust                    | Extended Stay America Trust 2021-ESH                                                                                   | CUSIP: 30227FAA8<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    390477 | PA      | $379211.33    | 0.38%             | 2038-07-15      | Floating      | 5.40%                 | No            |                  2 | On Loan: No      |
| Worldwide Plaza Trust                          | Worldwide Plaza Trust 2017-WWP                                                                                         | CUSIP: 98162JAA4<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    100000 | PA      | $85755.28     | 0.09%             | 2036-11-10      | Fixed         | 3.53%                 | No            |                  2 | On Loan: No      |
| TENN VALLEY AUTH                               | Tennessee Valley Authority Principal Strip                                                                             | CUSIP: 88059FBG5<br>LEI: 549300HE1ISW43LNKM54 | Long             | DBT              | USGA              | US        |    500000 | PA      | $363179.28    | 0.36%             | 2030-05-01      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810RP5<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |    370000 | PA      | $304353.90    | 0.30%             | 2045-11-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| JPMorgan Securities LLC                        | 31750KMK5 OPTION                                                                                                       | CUSIP: 000000000<br>LEI: ZBUT11V806EZRVTWT807 | N/A              | DIR              |  | US        |  -2600000 | NC      | $-6580.86     | -0.01%            |  |  |  | No            |                  2 | On Loan: No      |
| Freddie Mac                                    | Freddie Mac REMICS                                                                                                     | CUSIP: 3137AT2J0<br>LEI: S6XOOCT0IEG5ABCC6L87 | Long             | ABS-MBS          | USGSE             | US        |   2200000 | PA      | $2015981.44   | 2.01%             | 2032-08-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Fannie Mae REMICS                                                                                                      | CUSIP: 31396VSR0<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |     64450 | PA      | $63165.54     | 0.06%             | 2037-05-25      | Fixed         | 4.25%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SX7<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   2300000 | PA      | $1650070.32   | 1.65%             | 2051-05-15      | Fixed         | 2.38%                 | No            |                  2 | On Loan: No      |
| Credit Suisse First Boston Mortgage Securities | CSFB Mortgage-Backed Pass-Through Certificates Series 2003-AR18                                                        | CUSIP: 22541QFC1<br>LEI: 549300506SI9CRFV9Z86 | Long             | ABS-MBS          | CORP              | US        |       269 | PA      | $254.81       | 0.00%             | 2033-07-25      | Variable      | 3.14%                 | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Federal National Mortgage Association                                                                                  | CUSIP: 31364FYC9<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | DBT              | USGSE             | US        |    100000 | PA      | $106638.81    | 0.11%             | 2028-04-17      | Fixed         | 5.63%                 | No            |                  2 | On Loan: No      |
| Chicago Board of Trade                         | US 10YR NOTE (CBT)MAR23                                                                                                | CUSIP: 000000000<br>LEI: 549300EX04Q2QBFQTQ27 | N/A              | DIR              |  | US        |        52 | NC      | $-13883.74    | -0.01%            |  |  |  | No            |                  1 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810RM2<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1620000 | PA      | $1334601.55   | 1.33%             | 2045-05-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810TK4<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   6500000 | PA      | $5809375.00   | 5.80%             | 2042-08-15      | Fixed         | 3.38%                 | No            |                  2 | On Loan: No      |
| Freddie Mac                                    | Freddie Mac REMICS                                                                                                     | CUSIP: 3137BDY34<br>LEI: S6XOOCT0IEG5ABCC6L87 | Long             | ABS-MBS          | USGSE             | US        |   2419750 | PA      | $2292276.18   | 2.29%             | 2044-09-15      | Fixed         | 4.00%                 | No            |                  2 | On Loan: No      |
| Government National Mortgage Association       | Government National Mortgage Association                                                                               | CUSIP: 38376VKK2<br>LEI: 549300M8ZYFG0OCMTT87 | Long             | ABS-MBS          | USGA              | US        |    304709 | PA      | $247830.55    | 0.25%             | 2040-02-20      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| Chicago Mercantile Exchange                    | Long: SWU012TP6 IRS USD R F  1.25000 SWU012TP6 CCPVANILLA / Short: SWU012TP6 IRS USD P V 03MLIBOR SWUV12TP8 CCPVANILLA | CUSIP: 000000000<br>LEI: SNZ2OJLFK8MNNCLQOF39 | N/A              | DIR              |  | US        |   1400000 | OU      | $-573414.10   | -0.57%            |  |  |  | No            |                  2 | On Loan: No      |
| RESOLUTION FUNDING STRIP                       | Resolution Funding Corp Interest Strip                                                                                 | CUSIP: 76116EHK9<br>LEI: N/A                  | Long             | DBT              | USGA              | US        |    400000 | PA      | $318465.35    | 0.32%             | 2028-04-15      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| Hertz Vehicle Financing LLC                    | Hertz Vehicle Financing LLC                                                                                            | CUSIP: 42806MAN9<br>LEI: 5493004IHDYOZ9K9WF47 | Long             | ABS-O            | CORP              | US        |    300000 | PA      | $262958.13    | 0.26%             | 2028-06-26      | Fixed         | 2.33%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SD1<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |    700000 | PA      | $574820.32    | 0.57%             | 2048-08-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| Freddie Mac                                    | Freddie Mac REMICS                                                                                                     | CUSIP: 3137A2SY8<br>LEI: S6XOOCT0IEG5ABCC6L87 | Long             | ABS-MBS          | USGSE             | US        |     21717 | PA      | $21227.17     | 0.02%             | 2040-11-15      | Floating      | 4.82%                 | No            |                  2 | On Loan: No      |
| Government National Mortgage Association       | Ginnie Mae                                                                                                             | CUSIP: 21H040616<br>LEI: 549300M8ZYFG0OCMTT87 | Long             | ABS-MBS          | USGA              | US        |    800000 | PA      | $756877.95    | 0.76%             | 2053-01-23      | Fixed         | 4.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SZ2<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   4300000 | PA      | $2815492.17   | 2.81%             | 2051-08-15      | Fixed         | 2.00%                 | No            |                  2 | On Loan: No      |
| Freddie Mac                                    | Freddie Mac REMICS                                                                                                     | CUSIP: 31394RLM9<br>LEI: S6XOOCT0IEG5ABCC6L87 | Long             | ABS-MBS          | USGSE             | US        |    113306 | PA      | $113810.16    | 0.11%             | 2034-02-15      | Fixed         | 5.50%                 | No            |                  2 | On Loan: No      |
| COMM Mortgage Trust                            | COMM 2018-HOME Mortgage Trust                                                                                          | CUSIP: 20048JAA8<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    200000 | PA      | $181612.12    | 0.18%             | 2033-04-10      | Variable      | 3.82%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SR0<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   6790000 | PA      | $4249585.19   | 4.24%             | 2040-05-15      | Fixed         | 1.13%                 | No            |                  2 | On Loan: No      |
| LCH Limited                                    | Long: BWU015JB1 IRS USD R V 03MLIBOR SWUV15JB3 CCPVANILLA / Short: BWU015JB1 IRS USD P F   .75000 SWU015JB1 CCPVANILLA | CUSIP: 000000000<br>LEI: F226TOH6YD6XJB17KS62 | N/A              | DIR              |  | US        |   1000000 | OU      | $218739.20    | 0.22%             |  |  |  | No            |                  2 | On Loan: No      |
| Massachusetts Educational Financing Authority  | Massachusetts Educational Financing Authority                                                                          | CUSIP: 57563NAA6<br>LEI: 5493007K5OP7V6CL0Y88 | Long             | ABS-O            | CORP              | US        |     23134 | PA      | $23036.00     | 0.02%             | 2038-04-25      | Floating      | 5.31%                 | No            |                  2 | On Loan: No      |
| COMM Mortgage Trust                            | COMM 2016-667M Mortgage Trust                                                                                          | CUSIP: 12636GAA9<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    700000 | PA      | $610593.20    | 0.61%             | 2036-10-10      | Fixed         | 3.14%                 | No            |                  2 | On Loan: No      |
| VNO Mortgage Trust                             | VNDO Trust 2016-350P                                                                                                   | CUSIP: 91831UAA5<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    800000 | PA      | $724936.80    | 0.72%             | 2035-01-10      | Fixed         | 3.81%                 | No            |                  2 | On Loan: No      |
| Structured Asset Mortgage Investments Inc      | Structured Asset Mortgage Investments II Trust 2004-AR5                                                                | CUSIP: 86359LDX4<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |      1604 | PA      | $1492.85      | 0.00%             | 2034-10-19      | Floating      | 5.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810TJ7<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   4500000 | PA      | $3707578.13   | 3.70%             | 2052-08-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Fannie Mae Pool                                                                                                        | CUSIP: 3138L8YJ7<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |    561451 | PA      | $527011.14    | 0.53%             | 2040-02-01      | Fixed         | 3.60%                 | No            |                  2 | On Loan: No      |
| Chicago Board of Trade                         | US 2YR NOTE (CBT) MAR23                                                                                                | CUSIP: 000000000<br>LEI: 549300EX04Q2QBFQTQ27 | N/A              | DIR              |  | US        |        51 | NC      | $-463.08      | -0.00%            |  |  |  | No            |                  1 | On Loan: No      |
| ReadyCap Commercial Mortgage Trust             | Ready Capital Mortgage Financing 2022-FL8 LLC                                                                          | CUSIP: 75574PAA0<br>LEI: N/A                  | Long             | ABS-CBDO         | CORP              | US        |    200000 | PA      | $194439.38    | 0.19%             | 2037-01-25      | Floating      | 5.59%                 | No            |                  2 | On Loan: No      |
| Morgan Stanley Capital I Trust                 | Morgan Stanley Capital I Trust 2021-230P                                                                               | CUSIP: 61772WAA5<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    200000 | PA      | $191052.64    | 0.19%             | 2023-12-15      | Floating      | 5.49%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SQ2<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |  65580000 | PA      | $40726204.36  | 40.67%            | 2040-08-15      | Fixed         | 1.13%                 | No            |                  2 | On Loan: No      |
| DBWF Mortgage Trust                            | DBWF 2016-85T Mortgage Trust                                                                                           | CUSIP: 23307CAA3<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    800000 | PA      | $720539.12    | 0.72%             | 2036-12-10      | Fixed         | 3.79%                 | No            |                  2 | On Loan: No      |
| Chicago Board of Trade                         | US 5YR NOTE (CBT) MAR23                                                                                                | CUSIP: 000000000<br>LEI: 549300EX04Q2QBFQTQ27 | N/A              | DIR              |  | US        |      -174 | NC      | $-2859.86     | -0.00%            |  |  |  | No            |                  1 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810RQ3<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |    940000 | PA      | $703310.93    | 0.70%             | 2046-02-15      | Fixed         | 2.50%                 | No            |                  2 | On Loan: No      |
| Chicago Mercantile Exchange                    | Long: SWU012TN1 IRS USD R F  1.00000 SWU012TN1 CCPVANILLA / Short: SWU012TN1 IRS USD P V 03MLIBOR SWUV12TN3 CCPVANILLA | CUSIP: 000000000<br>LEI: SNZ2OJLFK8MNNCLQOF39 | N/A              | DIR              |  | US        |   3170000 | OU      | $-292789.76   | -0.29%            |  |  |  | No            |                  2 | On Loan: No      |
| Hilton USA Trust                               | Hilton USA Trust 2016-HHV                                                                                              | CUSIP: 43300LAJ9<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    400000 | PA      | $360025.04    | 0.36%             | 2038-11-05      | Variable      | 4.19%                 | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Fannie Mae Pool                                                                                                        | CUSIP: 31402RFV6<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |     22644 | PA      | $23123.71     | 0.02%             | 2035-06-01      | Fixed         | 5.00%                 | No            |                  2 | On Loan: No      |
| US TREASURY N/B                                | United States Treasury Note/Bond                                                                                       | CUSIP: 912810RJ9<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1620000 | PA      | $1337006.25   | 1.34%             | 2044-11-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810RH3<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1620000 | PA      | $1368836.72   | 1.37%             | 2044-08-15      | Fixed         | 3.13%                 | No            |                  2 | On Loan: No      |
| Freddie Mac                                    | Freddie Mac REMICS                                                                                                     | CUSIP: 3137BERC0<br>LEI: S6XOOCT0IEG5ABCC6L87 | Long             | ABS-MBS          | USGSE             | US        |    831352 | PA      | $742206.55    | 0.74%             | 2054-09-15      | Fixed         | 4.00%                 | No            |                  2 | On Loan: No      |
| BWAY Mortgage Trust                            | BWAY 2013-1515 Mortgage Trust                                                                                          | CUSIP: 05604FAC9<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    300000 | PA      | $280145.73    | 0.28%             | 2033-03-10      | Fixed         | 3.45%                 | No            |                  2 | On Loan: No      |
| Chicago Mercantile Exchange                    | Long: SWU01D5I4 IRS USD R F  1.60000 SWU01D5I4 CCPOIS / Short: SWU01D5I4 IRS USD P V 12MSOFR SWUV1D5I6 CCPOIS          | CUSIP: 000000000<br>LEI: SNZ2OJLFK8MNNCLQOF39 | N/A              | DIR              |  | US        |   9000000 | OU      | $-736956.00   | -0.74%            |  |  |  | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Strip Coupon                                                                                    | CUSIP: 9128334Y3<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |    850000 | PA      | $526289.60    | 0.53%             | 2034-08-15      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SP4<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   3300000 | PA      | $1833691.40   | 1.83%             | 2050-08-15      | Fixed         | 1.38%                 | No            |                  2 | On Loan: No      |
| New Residential Mortgage Loan Trust            | New Residential Mortgage Loan Trust 2020-RPL1                                                                          | CUSIP: 64828XAA1<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    103776 | PA      | $94569.14     | 0.09%             | 2059-11-25      | Variable      | 2.75%                 | No            |                  2 | On Loan: No      |
| Morgan Stanley Mortgage Capital Holdings LLC   | MSSG Trust 2017-237P                                                                                                   | CUSIP: 55375KAS5<br>LEI: N/A                  | Long             | ABS-MBS          | CORP              | US        |    700000 | PA      | $613773.51    | 0.61%             | 2039-09-13      | Fixed         | 3.40%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Inflation Indexed Bonds                                                                         | CUSIP: 91282CEZ0<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |   1230540 | PA      | $1127072.12   | 1.13%             | 2032-07-15      | Fixed         | 0.63%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SA7<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |    330000 | PA      | $270483.99    | 0.27%             | 2048-02-15      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Fannie Mae REMICS                                                                                                      | CUSIP: 3136ATQS6<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |    900000 | PA      | $752419.17    | 0.75%             | 2046-09-25      | Fixed         | 3.00%                 | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Fannie Mae Pool                                                                                                        | CUSIP: 31403C6L0<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |     34776 | PA      | $35450.41     | 0.04%             | 2036-02-01      | Fixed         | 5.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810ST6<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |  11200000 | PA      | $7281312.53   | 7.27%             | 2040-11-15      | Fixed         | 1.38%                 | No            |                  2 | On Loan: No      |
| JPMorgan Securities LLC                        | 3175544B6 OPTION                                                                                                       | CUSIP: 000000000<br>LEI: ZBUT11V806EZRVTWT807 | N/A              | DIR              |  | US        |  -2600000 | NC      | $-39993.20    | -0.04%            |  |  |  | No            |                  2 | On Loan: No      |
| Fannie Mae                                     | Fannie Mae Pool                                                                                                        | CUSIP: 31418DDL3<br>LEI: B1V7KEBTPIMZEU4LTD58 | Long             | ABS-MBS          | USGSE             | US        |     29912 | PA      | $30432.98     | 0.03%             | 2049-05-01      | Fixed         | 5.50%                 | No            |                  2 | On Loan: No      |
| LCH Limited                                    | Long: BWU0177O2 IRS USD R V 03MLIBOR SWUV177O4 CCPVANILLA / Short: BWU0177O2 IRS USD P F  1.25000 SWU0177O2 CCPVANILLA | CUSIP: 000000000<br>LEI: F226TOH6YD6XJB17KS62 | N/A              | DIR              |  | US        |   3110000 | OU      | $1051391.79   | 1.05%             |  |  |  | No            |                  2 | On Loan: No      |
| United States Treasury                         | United States Treasury Note/Bond                                                                                       | CUSIP: 912810SS8<br>LEI: 254900HROIFWPRGM1V77 | Long             | DBT              | UST               | US        |    400000 | PA      | $238000.00    | 0.24%             | 2050-11-15      | Fixed         | 1.63%                 | No            |                  2 | On Loan: No      |

### Signature

**Date Signed:** 2023-03-10

**Name of Applicant:** NORTHWESTERN MUTUAL SERIES FUND INC

**Signature:** Phillip Rinzel

**Name of Signer:** Phillip Rinzel

**Title:** Controller and Chief Accounting Officer