# EDGAR Filing Document

**Accession Number:** 0000742212
**File Stem:** 0001410368-26-016308
**Filing Date:** 2026-2
**Character Count:** 16741
**Document Hash:** f31540e3b51fae0aa4b30d745e8e4ffd
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001410368-26-016308.hdr.sgml**: 20260223

**ACCESSION NUMBER**: 0001410368-26-016308

**CONFORMED SUBMISSION TYPE**: NPORT-P

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260223

**DATE AS OF CHANGE**: 20260223

**PERIOD START**: 20251231

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** NORTHWESTERN MUTUAL SERIES FUND INC
- **CENTRAL INDEX KEY:** 0000742212

**ORGANIZATION NAME:**
- **EIN:** 391603401
- **STATE OF INCORPORATION:** MD
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** NPORT-P
- **SEC ACT:** 1940 Act
- **SEC FILE NUMBER:** 811-03990
- **FILM NUMBER:** 26664749

**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

### Active/Passive Moderate Portfolio (Series ID: S000000044)

| Class ID   | Class Name                        | Ticker Symbol   |
|:---|:---|:---|
| C000000079 | Active/Passive Moderate 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:** Active/Passive Moderate Portfolio

- **b. EDGAR series identifier (if any):** S000000044

- **c. LEI of Series:** 5DD2LVSRPBY8KFA02K39

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

- **a. Date of fiscal year-end:** 2025-12-31

- **b. Date as of which information is reported:** 2025-12-31

**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:** $299082057.02

**Total Liabilities:** $54141.72

**Net Assets:** $299027915.30

**Cash Not Reported:** $2980171.96

**Monthly Return Information**

| Class               | Month 1 Return (%)   | Month 2 Return (%)   | Month 3 Return (%)   |
|:---|:---|:---|:---|
| Class ID C000000079 | 0.84%                | 0.75%                | 0.50%                |

**Monthly Gains & Losses**

| Period   | Net Realized Gain/Loss   | Net Unrealized Appreciation/Depreciation   |
|:---|:---|:---|
| Month 1  | $-44697.17               | $2524275.08                                |
| Month 2  | $565861.56               | $1344508.95                                |
| Month 3  | $710806.24               | $-213668.83                                |

### 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   |
|:---|:---|:---|:---|:---|:---|:---|---:|:---|:---|:---|:---|:---|:---|:---|---:|:---|
| abrdn Bloomberg All Commodity Strategy K-1 Free ETF                       | abrdn Bloomberg All Commodity Strategy K-1 Free ETF                                    | CUSIP: 003261104<br>LEI: 549300PWXO8WGDSMS419 | Long             | EC               | RF                | US        |     34290 | NS      | $669683.70    | 0.22%             |  |  |  | No            |                  1 | On Loan: No      |
| Dimensional International Value ETF                                       | Dimensional International Value ETF                                                    | CUSIP: 25434V807<br>LEI: 549300F3EUNKP4DGBS58 | Long             | EC               | RF                | US        |     66500 | NS      | $3318350.00   | 1.11%             |  |  |  | No            |                  1 | On Loan: No      |
| Invesco S&P 500 Equal Weight ETF                                          | Invesco S&P 500 Equal Weight ETF                                                       | CUSIP: 46137V357<br>LEI: 549300F8VBQFIX481R47 | Long             | EC               | RF                | US        |     46890 | NS      | $8982248.40   | 3.00%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares Core S&P 500 ETF                                                  | iShares Core S&P 500 ETF                                                               | CUSIP: 464287200<br>LEI: 5493007M4YMN8XL48C14 | Long             | EC               | RF                | US        |     40390 | NS      | $27664726.60  | 9.25%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares Core U.S. Aggregate Bond ETF                                      | iShares Core U.S. Aggregate Bond ETF                                                   | CUSIP: 464287226<br>LEI: 549300F7VSXTKBGHJE47 | Long             | EC               | RF                | US        |    225771 | NS      | $22550007.48  | 7.54%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares MSCI USA Value Factor ETF                                         | iShares MSCI USA Value Factor ETF                                                      | CUSIP: 46432F388<br>LEI: 549300QCMVXVCAPD3O82 | Long             | EC               | RF                | US        |     51830 | NS      | $7086715.90   | 2.37%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares Core MSCI EAFE ETF                                                | iShares Core MSCI EAFE ETF                                                             | CUSIP: 46432F842<br>LEI: 5493009FT582MI7Y3I36 | Long             | EC               | RF                | US        |    120640 | NS      | $10792454.40  | 3.61%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares MSCI International Quality Factor ETF                             | iShares MSCI International Quality Factor ETF                                          | CUSIP: 46434V456<br>LEI: 549300NCBUPWCYENVS18 | Long             | EC               | RF                | US        |    133830 | NS      | $6082573.50   | 2.03%             |  |  |  | No            |                  1 | On Loan: No      |
| JPMorgan Ultra-Short Income ETF                                           | JPMorgan Ultra-Short Income ETF                                                        | CUSIP: 46641Q837<br>LEI: 549300VN24B8TQAGGX74 | Long             | EC               | RF                | US        |     59520 | NS      | $3011116.80   | 1.01%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Large Cap Blend Portfolio         | LARGE CAP BLEND PORT                                                                   | CUSIP: 668140205<br>LEI: 549300J8IDGQV6XROU84 | Long             | EC               | RF                | US        |  10289358 | NS      | $11596106.18  | 3.88%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Emerging Markets Equity Portfolio | MFS EMERGING MKTS PORT                                                                 | CUSIP: 668140502<br>LEI: 549300B2SFS01R9MCJ10 | Long             | EC               | RF                | US        |   9399245 | NS      | $11946440.10  | 4.00%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Short-Term Bond Portfolio.        | Short Term Bond Portolio                                                               | CUSIP: 668140601<br>LEI: BEEDB5U9NNUVQYFFEL15 | Long             | EC               | RF                | US        |   2834799 | NS      | $2979373.77   | 1.00%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - International Growth Portfolio    | International Growth Portfolio                                                         | CUSIP: 668140684<br>LEI: A7EFFZCFPQNSS1P3HZ68 | Long             | EC               | RF                | US        |   4756281 | NS      | $10454305.76  | 3.50%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - International Equity Portfolio    | International Equity Portfolio                                                         | CUSIP: 668140692<br>LEI: 5493009J2EF7GK480170 | Long             | EC               | RF                | US        |   8469348 | NS      | $18022772.42  | 6.03%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Select Bond Portfolio             | Select Bond Portfolio                                                                  | CUSIP: 668140759<br>LEI: 03DZ35VFRGD62UKLL347 | Long             | EC               | RF                | US        |  48107215 | NS      | $53447115.41  | 17.87%            |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Focused Appreciation Portfolio    | FOCUSED APPRECIATION PORTFOLIO                                                         | CUSIP: 668140775<br>LEI: 5493007QO6Z6UMWHLZ04 | Long             | EC               | RF                | US        |   2455705 | NS      | $11613028.52  | 3.88%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Mid Cap Value Portfolio           | MID CAP VALUE PORTFOLIO                                                                | CUSIP: 668140783<br>LEI: 8TRVIGMWHSWZVXP7PI34 | Long             | EC               | RF                | US        |   3425313 | NS      | $5220177.06   | 1.75%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Domestic Equity Portfolio         | DOMESTIC EQUITY PORTFOLIO                                                              | CUSIP: 668140791<br>LEI: 5493004TKKI7X6F71K84 | Long             | EC               | RF                | US        |   7565137 | NS      | $11862134.09  | 3.97%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Small Cap Value Portfolio         | SMALL CAP VALUE PORTFOLIO                                                              | CUSIP: 668140817<br>LEI: 5493006BEZYY47A02J59 | Long             | EC               | RF                | US        |   1575496 | NS      | $3072216.75   | 1.03%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Small Cap Growth Stock Portfolio  | SMALL CAP GROWTH STK PORTFOLIO                                                         | CUSIP: 668140825<br>LEI: YTR2S467AP5XPLF6CQ13 | Long             | EC               | RF                | US        |   1163273 | NS      | $2980304.52   | 1.00%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Mid Cap Growth Stock Portfolio    | MID CAP GROWTH PORTFOLIO                                                               | CUSIP: 668140866<br>LEI: LIP0ME8UWTR611J45283 | Long             | EC               | RF                | US        |   1701074 | NS      | $5195079.67   | 1.74%             |  |  |  | No            |                  1 | On Loan: No      |
| Northwestern Mutual Series Fund, Inc. - Multi-Sector Bond Portfolio       | PIMCO MULTI SECTOR BD PORT MUTUAL FUND                                                 | CUSIP: 668140882<br>LEI: P0C14V6IL3O47L1ZG636 | Long             | EC               | RF                | US        |  14674890 | NS      | $15041762.69  | 5.03%             |  |  |  | No            |                  1 | On Loan: No      |
| State Street SPDR Dow Jones REIT ETF                                      | State Street SPDR Dow Jones REIT ETF                                                   | CUSIP: 78464A607<br>LEI: 54930077YVRJPO64VF50 | Long             | EC               |  | US        |     45430 | NS      | $4462588.90   | 1.49%             |  |  |  | No            |                  1 | On Loan: No      |
| State Street SPDR Portfolio Long Term Treasury ETF                        | State Street SPDR Portfolio Long Term Treasury ETF                                     | CUSIP: 78464A664<br>LEI: 549300GYQKAMF6JUVI06 | Long             | EC               | RF                | US        |    219320 | NS      | $5805400.40   | 1.94%             |  |  |  | No            |                  1 | On Loan: No      |
| State Street SPDR Portfolio S&P 400 Mid Cap ETF                           | State Street SPDR Portfolio S&P 400 Mid Cap ETF                                        | CUSIP: 78464A847<br>LEI: 549300TKUU0ZLRVSLJ96 | Long             | EC               | RF                | US        |    244690 | NS      | $14169997.90  | 4.74%             |  |  |  | No            |                  1 | On Loan: No      |
| State Street SPDR Portfolio S&P 600 Small Cap ETF                         | State Street SPDR Portfolio S&P 600 Small Cap ETF                                      | CUSIP: 78468R853<br>LEI: 549300NYZX301TBLUJ08 | Long             | EC               | RF                | US        |    155950 | NS      | $7307817.00   | 2.44%             |  |  |  | No            |                  1 | On Loan: No      |
| Schwab U.S. REIT ETF                                                      | Schwab U.S. REIT ETF                                                                   | CUSIP: 808524847<br>LEI: 549300OLDKO120DR6467 | Long             | EC               |  | US        |    213800 | NS      | $4466282.00   | 1.49%             |  |  |  | No            |                  1 | On Loan: No      |
| United States Treasury                                                    | U.S. Treasury Bills                                                                    | CUSIP: 912797RK5<br>LEI: 254900HROIFWPRGM1V77 | Long             | STIV             | UST               | US        |   2000000 | PA      | $1994718.42   | 0.67%             | 2026-01-29      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                                                    | U.S. Treasury Bills                                                                    | CUSIP: 912797RU3<br>LEI: 254900HROIFWPRGM1V77 | Long             | STIV             | UST               | US        |   2000000 | PA      | $1989034.46   | 0.67%             | 2026-02-26      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                                                    | U.S. Treasury Bills                                                                    | CUSIP: 912797TB3<br>LEI: 254900HROIFWPRGM1V77 | Long             | STIV             | UST               | US        |   2300000 | PA      | $2280234.24   | 0.76%             | 2026-03-31      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| Citibank NA                                                               | Long: 540169    TRS USD R E REC EQUITY / Short: 540169    TRS USD P F   .12000 PAY FIX | CUSIP: 000000000<br>LEI: E57ODZWZ7FF32TWEFA76 | N/A              | DCO              |  | US        |   6872321 | OU      | $24508.29     | 0.01%             |  |  |  | No            |                  2 | On Loan: No      |

### Signature

**Date Signed:** 2026-01-15

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

**Signature:** Linda Wisniewski

**Name of Signer:** Linda Wisniewski

**Title:** Controller and Chief Accounting Officer