Mason Street Advisors, LLC
In its 13F for Q4 2025 (holdings as of December 31, 2025, filed February 4, 2026), Mason Street Advisors, LLC reported 15 stock positions worth $1.0 billion. Its top holding was iShares Core U.S. Aggregate (AGG) at 30.5% of the portfolio, followed by iShares Core S&P 500 ETF (IVV, 14.2%) and SS SPDR PF LNG TRM TSY E-Usd (SPTL, 10.4%). Compared with Q3 2025, it opened 2 new positions, sold out of 2, added to 9 and reduced 4. The biggest buy was a new position in iShares Core S&P Small-Cap E (IJR) and the biggest sale iShares Core MSCI Eafe ETF (IEFA, shares −99%).
- Most Recent 13F
- Q2 2026
- Location
- MILWAUKEE, WI
- CIK
- 0001167711
- Portfolio Value
- $1.0B (Q4 2025)
- SEC Filing
- 0001167711-26-000001 ↗ filed Feb 4, 2026
Holdings Value
Holdings 15 stocks · $1.0B
| AGG iShares Core U.S. Aggregate | 30.54% | 3,107,230 | $310.4M | Add +2.2% |
| IVV iShares Core S&P 500 ETF | 14.21% | 210,793 | $144.4M | Add +0.5% |
| SPTL SS SPDR PF LNG TRM TSY E-Usd | 10.41% | 3,997,680 | $105.8M | Add +0.9% |
| SPMD SS SPDR P S&P 400 Midcap ETF | 9.04% | 1,587,390 | $91.9M | Add +16.5% |
| SPSM SS SPDR P S&P 600 Small Cap | 5.97% | 1,293,880 | $60.6M | Add +11.2% |
| IJR iShares Core S&P Small-Cap E | 5.62% | 639,005 | $57.2M | New |
| RSP Invesco S&P 500 Equal Weight | 4.89% | 259,430 | $49.7M | Add +70.0% |
| IJH iShares Core S&P Midcap ETF | 3.90% | 289,860 | $39.6M | New |
| RWR SS SPDR Dow Jones REIT ETF | 3.54% | 366,555 | $36.0M | Add +3.0% |
| SCHH Schwab US REIT ETF | 3.52% | 1,713,085 | $35.8M | Add +5.3% |
| IQLT iShares MSCI International Q | 3.35% | 748,240 | $34.0M | Reduce -0.4% |
| JPST JPMorgan Ultra-Short Income | 2.39% | 480,735 | $24.3M | Add +2.6% |
| DFIV Dimensional International Va | 1.93% | 393,365 | $19.6M | Reduce -11.2% |
| BCI Abrdn Bloomberg All Commodit filed as ABRDN ETFS | 0.65% | 337,715 | $6.6M | Reduce -15.5% |
| IEFA iShares Core MSCI Eafe ETF | 0.04% | 5,700 | $383K | Reduce -99.1% |
Portfolio Sells Q3 2025 → Q4 2025
| IEFA iShares Core MSCI Eafe ETF | Reduce -99.1% | 0.04% | −5.68 |
| VLUE iShares MSCI USA Value Facto | Sold out | 0.00% | −4.15 |
| BCI Abrdn Bloomberg All Commodit | Reduce -15.5% | 0.65% | −0.24 |
| DFIV Dimensional International Va | Reduce -11.2% | 1.93% | −0.19 |
| IQLT iShares MSCI International Q | Reduce -0.4% | 3.35% | −0.10 |
| IEMG iShares Core MSCI Emerging | Sold out | 0.00% | −0.02 |
Portfolio Buys Q3 2025 → Q4 2025
| IJR iShares Core S&P Small-Cap E | New | 5.62% | +5.62 |
| IJH iShares Core S&P Midcap ETF | New | 3.90% | +3.90 |
| RSP Invesco S&P 500 Equal Weight | Add +70.0% | 4.89% | +1.89 |
| SPMD SS SPDR P S&P 400 Midcap ETF | Add +16.5% | 9.04% | +0.97 |
| SPSM SS SPDR P S&P 600 Small Cap | Add +11.2% | 5.97% | +0.38 |
| JPST JPMorgan Ultra-Short Income | Add +2.6% | 2.39% | −0.07 |
| SCHH Schwab US REIT ETF | Add +5.3% | 3.52% | −0.12 |
| RWR SS SPDR Dow Jones REIT ETF | Add +3.0% | 3.54% | −0.16 |
| IVV iShares Core S&P 500 ETF | Add +0.5% | 14.21% | −0.34 |
| SPTL SS SPDR PF LNG TRM TSY E-Usd | Add +0.9% | 10.41% | −0.66 |
| AGG iShares Core U.S. Aggregate | Add +2.2% | 30.54% | −1.05 |
All Filings
| Quarter | Positions | 13F Reported Value | Top Holdings |
|---|---|---|---|
| Q2 2026 | 15 | $1.1B | AGG, IVV, SPTL, SPMD, SPSM |
| Q1 2026 | 15 | $1.0B | AGG, IVV, SPTL, SPMD, IEFA |
| Q4 2025 | 15 | $1.0B | AGG, IVV, SPTL, SPMD, SPSM |
| Q3 2025 | 15 | $964.8M | AGG, IVV, SPTL, SPMD, IEFA |
| Q2 2025 | 15 | $854.5M | AGG, IVV, SPTL, SPMD, IEFA |
| Q1 2025 | 13 | $786.1M | AGG, IVV, SPTL, IEFA, SPMD |
| Q4 2024 | 12 | $772.6M | AGG, IVV, SPTL, IEFA, SPMD |
| Q3 2024 | 12 | $823.5M | AGG, IVV, SPTL, IEFA, SPMD |
| Q2 2024 | 12 | $743.0M | AGG, IVV, SPTL, IEFA, SCHH |
| Q1 2024 | 8 | $594.2M | IVV, AGG, IEFA, JPST, MINT |