# EDGAR Filing Document

**Accession Number:** 0000742212
**File Stem:** 0001752724-25-192584
**Filing Date:** 2025-8
**Character Count:** 17937
**Document Hash:** a7ae4c20c2ca3bcbc5a91dbe3a13aeb7
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001752724-25-192584.hdr.sgml**: 20250819

**ACCESSION NUMBER**: 0001752724-25-192584

**CONFORMED SUBMISSION TYPE**: NPORT-P

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250630

**FILED AS OF DATE**: 20250819

**DATE AS OF CHANGE**: 20250819

**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:** 251231266

**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 Balanced Portfolio (Series ID: S000000045)

| Class ID   | Class Name                        | Ticker Symbol   |
|:---|:---|:---|
| C000000080 | Active/Passive Balanced 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:** Balanced Portfolio

- **b. EDGAR series identifier (if any):** S000000045

- **c. LEI of Series:** 4F2ZSMZDZU02NP7J8L64

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

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

- **b. Date as of which information is reported:** 2025-06-30

**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:** $1936646987.91

**Total Liabilities:** $1032285.11

**Net Assets:** $1935614702.80

**Cash Not Reported:** $24348357.75

**Monthly Return Information**

| Class               | Month 1 Return (%)   | Month 2 Return (%)   | Month 3 Return (%)   |
|:---|:---|:---|:---|
| Class ID C000000080 | -0.07%               | 1.94%                | 2.64%                |

**Monthly Gains & Losses**

| Period   | Net Realized Gain/Loss   | Net Unrealized Appreciation/Depreciation   |
|:---|:---|:---|
| Month 1  | $-1404758.21             | $288341.10                                 |
| Month 2  | $5859268.40              | $28961887.23                               |
| Month 3  | $7221745.36              | $37707741.06                               |

**Designated Index Information**

- **Index Name:** Balanced Portfolio Blended Composite Benchmark

- **Index Identifier:** SPXT, SPTRMDCP, SPTRSMCP, NDDUEAFE, NDUEEGF, DWRTFT, BCOMTR, LBUSTRUU, G0O1

### 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   |
|:---|:---|:---|:---|:---|:---|:---|---:|:---|:---|:---|:---|:---|:---|:---|---:|:---|
| JPMorgan Ultra-Short Income ETF                                           | JPMorgan Ultra-Short Income ETF                                                                         | CUSIP: 46641Q837<br>LEI: 549300VN24B8TQAGGX74 | Long             | EC               | RF                | US        |    188550 | NS      | $9555714.00   | 0.49%             |  |  |  | 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        |  21532684 | NS      | $47458034.55  | 2.45%             |  |  |  | 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        |  31008031 | NS      | $48372528.56  | 2.50%             |  |  |  | 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        |   9874493 | NS      | $50201920.69  | 2.59%             |  |  |  | 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        |   2501800 | NS      | $248178560.00 | 12.82%            |  |  |  | No            |                  1 | On Loan: No      |
| iShares MSCI Intl Quality Factor ETF                                      | iShares MSCI Intl Quality Factor ETF                                                                    | CUSIP: 46434V456<br>LEI: 549300NCBUPWCYENVS18 | Long             | EC               | RF                | US        |    563600 | NS      | $24358792.00  | 1.26%             |  |  |  | No            |                  1 | On Loan: No      |
| Schwab U.S. REIT ETF                                                      | Schwab U.S. REIT ETF                                                                                    | CUSIP: 808524847<br>LEI: 549300OLDKO120DR6467 | Long             | EC               | RF                | US        |   1297100 | NS      | $27446636.00  | 1.42%             |  |  |  | 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        | 442886748 | NS      | $498690478.41 | 25.76%            |  |  |  | No            |                  1 | On Loan: No      |
| 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        |    258400 | NS      | $5366968.00   | 0.28%             |  |  |  | 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        | 140192401 | NS      | $144538365.56 | 7.47%             |  |  |  | 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        |  40291421 | NS      | $78769727.61  | 4.07%             |  |  |  | No            |                  1 | On Loan: No      |
| SPDR Portfolio Long Term Treasury ETF                                     | SPDR Portfolio Long Term Treasury ETF                                                                   | CUSIP: 78464A664<br>LEI: 549300GYQKAMF6JUVI06 | Long             | EC               | RF                | US        |   3663300 | NS      | $97370514.00  | 5.03%             |  |  |  | No            |                  1 | On Loan: No      |
| Dimensional International Value ETF                                       | Dimensional International Value ETF                                                                     | CUSIP: 25434V807<br>LEI: 549300F3EUNKP4DGBS58 | Long             | EC               | RF                | US        |    348200 | NS      | $14913406.00  | 0.77%             |  |  |  | No            |                  1 | On Loan: No      |
| Morgan Stanley & Co. LLC                                                  | Long: 516499    TRS USD R E RECEIVE EQUITY / Short: 516499    TRS USD P F   .18000 PAY FIXED +0 PERCENT | CUSIP: 000000000<br>LEI: 9R7GPTSO7KV3UQJZQ078 | N/A              | DCO              |  | US        |  32815673 | OU      | $636130.32    | 0.03%             |  |  |  | No            |                  2 | On Loan: No      |
| United States Treasury                                                    | U.S. Treasury Bills                                                                                     | CUSIP: 912797QW0<br>LEI: 254900HROIFWPRGM1V77 | Long             | STIV             | UST               | US        |  11300000 | PA      | $11179649.58  | 0.58%             | 2025-09-30      | None          | 0.00%                 | No            |                  2 | On Loan: No      |
| United States Treasury                                                    | U.S. Treasury Bills                                                                                     | CUSIP: 912797QC4<br>LEI: 254900HROIFWPRGM1V77 | Long             | STIV             | UST               | US        |  11300000 | PA      | $11263526.09  | 0.58%             | 2025-07-29      | None          | 0.00%                 | No            |                  2 | 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        |    106400 | NS      | $19337136.00  | 1.00%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares Core S&P Small-Cap ETF                                            | iShares Core S&P Small-Cap ETF                                                                          | CUSIP: 464287804<br>LEI: 549300BZQ17QYN750B25 | Long             | EC               | RF                | US        |     39800 | NS      | $4349742.00   | 0.22%             |  |  |  | No            |                  1 | On Loan: No      |
| SPDR Portfolio S&P 400 Mid Cap ETF                                        | SPDR Portfolio S&P 400 Mid Cap ETF                                                                      | CUSIP: 78464A847<br>LEI: 549300TKUU0ZLRVSLJ96 | Long             | EC               | RF                | US        |    757200 | NS      | $41176536.00  | 2.13%             |  |  |  | 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        |  26871789 | NS      | $28725942.09  | 1.48%             |  |  |  | No            |                  1 | On Loan: No      |
| United States Treasury                                                    | U.S. Treasury Bills                                                                                     | CUSIP: 912797PQ4<br>LEI: 254900HROIFWPRGM1V77 | Long             | STIV             | UST               | US        |  11300000 | PA      | $11221260.92  | 0.58%             | 2025-08-28      | None          | 0.00%                 | No            |                  2 | 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        |  21351676 | NS      | $33543482.30  | 1.73%             |  |  |  | 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        |  64761865 | NS      | $69619005.35  | 3.60%             |  |  |  | No            |                  1 | On Loan: No      |
| SPDR Dow Jones REIT ETF                                                   | SPDR Dow Jones REIT ETF                                                                                 | CUSIP: 78464A607<br>LEI: 54930077YVRJPO64VF50 | Long             | EC               | RF                | US        |    279800 | NS      | $26983912.00  | 1.39%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares Core MSCI EAFE ETF                                                | iShares Core MSCI EAFE ETF                                                                              | CUSIP: 46432F842<br>LEI: 5493009FT582MI7Y3I36 | Long             | EC               | RF                | US        |    462400 | NS      | $38601152.00  | 1.99%             |  |  |  | No            |                  1 | On Loan: No      |
| iShares Core S&P Mid-Cap ETF                                              | iShares Core S&P Mid-Cap ETF                                                                            | CUSIP: 464287507<br>LEI: 549300ODQWH5PC0IUZ78 | Long             | EC               | RF                | US        |     91250 | NS      | $5659325.00   | 0.29%             |  |  |  | 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        |    226000 | NS      | $140323400.00 | 7.25%             |  |  |  | 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        |  12331375 | NS      | $24317470.55  | 1.26%             |  |  |  | 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        |   8989835 | NS      | $21674491.12  | 1.12%             |  |  |  | No            |                  1 | On Loan: No      |
| SPDR Portfolio S&P 600 Small Cap ETF                                      | SPDR Portfolio S&P 600 Small Cap ETF                                                                    | CUSIP: 78468R853<br>LEI: 549300NYZX301TBLUJ08 | Long             | EC               | RF                | US        |    946800 | NS      | $40333680.00  | 2.08%             |  |  |  | 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        |  42407468 | NS      | $49743960.48  | 2.57%             |  |  |  | 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        |  10472543 | NS      | $37544066.54  | 1.94%             |  |  |  | No            |                  1 | On Loan: No      |

### Signature

**Date Signed:** 2025-07-15

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

**Signature:** Linda Wisniewski

**Name of Signer:** Linda Wisniewski

**Title:** Controller and Chief Accounting Officer