Q2 2026 13F · SEC CIK 1167711
Mason Street Advisors, LLC
Mutual fund managerFiled 2026-08-12 for Q2 2026. Open the filing ↗ · All SEC filings ↗
- Reported 13F value
- $1.1B
- Reported positions
- 15
- Top holdings a year, 3 yrs
- +11.1%
- Assets under management
- $39.1B
Mason Street Advisors, LLC is a mutual fund manager that reported 15 positions worth $1.1B in its Q2 2026 13F, filed 2026-08-12. Its largest holdings were Ishares Tr (AGG, 27.2%), Ishares Tr (IVV, 13.9%), Spdr Series Trust (SPTL, 9.5%). A portfolio copying its top holdings returned 11.1% a year over the last 3 years, against 20.4% for the S&P 500.
Mason Street Advisors, LLC holdings all 15 positions.
Weights are shares of the filer's total reported 13F value, compared with Q1 2026. Share changes may reflect splits; weight changes also reflect price moves. A 13F shows long US-listed positions only, up to 135 days after the fact.
| Stock | % of 13F value | Share change | Reported value |
|---|---|---|---|
| AGGIshares Tr | 27.2% | +0.1% | $302.0M |
| IVVIshares Tr | 13.9% | -2.5% | $154.6M |
| SPTLSpdr Series Trust | 9.5% | +0.2% | $105.1M |
| SPMDSpdr Series Trust | 8.6% | -9.1% | $95.9M |
| SPSMSpdr Series Trust | 7.2% | +4.0% | $79.5M |
| RSPInvesco Exchange Traded Fd T | 5.5% | +7.8% | $61.4M |
| IEFAIshares Tr | 5.5% | -10.7% | $61.3M |
| RWRSpdr Series Trust | 4.6% | +30.0% | $51.2M |
| SCHHSchwab Strategic Tr | 4.6% | +31.3% | $51.2M |
| AVLVAmerican Centy ETF Tr | 3.9% | — | $43.3M |
| IQLTIshares Tr | 3.5% | +3.1% | $39.3M |
| JPSTJ P Morgan Exchange Traded F | 2.3% | +1.7% | $25.0M |
| DFIVDimensional ETF Trust | 2.0% | +2.7% | $22.4M |
| BCIAbrdn Etfs | 1.1% | +51.7% | $12.1M |
| IEMGIshares Inc | 0.5% | +56.4% | $5.6M |
What Mason Street Advisors, LLC bought and sold in Q2 2026, against Q1 2026.
New positions
- AVLV American Centy ETF Tr3.9% of 13F
Added to
- IEMG Ishares Inc+56.4% shares
- BCI Abrdn Etfs+51.7% shares
- SCHH Schwab Strategic Tr+31.3% shares
- RWR Spdr Series Trust+30.0% shares
- RSP Invesco Exchange Traded Fd T+7.8% shares
Reduced
- IEFA Ishares Tr-10.7% shares
- SPMD Spdr Series Trust-9.1% shares
Sold out
- VLUE Ishares Trwas 4.0%
Share counts compared with the Q1 2026 13F; a split also changes share counts.
How the holdings did against the S&P 500.
- 1 year
- +11.7% /yr
- S&P 500 +20.1%
- 3 years
- +11.1% /yr
- S&P 500 +20.4%
- 5 years
- +5.8% /yr
- S&P 500 +11.6%
A portfolio of the filer's 20 largest 13F positions, weighted by value, bought the trading day after each 13F was filed and held until the next one was: what copying this filer could have earned. 13Fs show long US-listed positions only, so this is an estimate of the stock picks, not the fund's reported returns.
Reported 13F value by quarter.
| Quarter | 13F value | Positions |
|---|---|---|
| Q2 2026 | $1.1B | 15 |
| Q1 2026 | $1.0B | 15 |
| Q4 2025 | $1.0B | 15 |
| Q3 2025 | $964.8M | 15 |
| Q2 2025 | $854.5M | 15 |
| Q1 2025 | $786.1M | 13 |
| Q4 2024 | $772.6M | 12 |
| Q3 2024 | $823.5M | 12 |
| Q2 2024 | $743.0M | 12 |
| Q1 2024 | $594.2M | 8 |
| Q4 2023 | $544.7M | 7 |
| Q3 2023 | $520.8M | 8 |
Questions about Mason Street Advisors, LLC's portfolio
What stocks does Mason Street Advisors, LLC own?
Mason Street Advisors, LLC's latest 13F, for Q2 2026 and filed Aug 12, 2026, lists 15 positions worth $1.1B. The largest are Ishares Tr (AGG) at 27.2%, Ishares Tr (IVV) at 13.9%, Spdr Series Trust (SPTL) at 9.5%, Spdr Series Trust (SPMD) at 8.6% and Spdr Series Trust (SPSM) at 7.2%.
What did Mason Street Advisors, LLC buy last quarter?
In Q2 2026, Mason Street Advisors, LLC added a new position in American Centy ETF Tr (AVLV), Ishares Inc (IEMG) (+56.4% shares), Abrdn Etfs (BCI) (+51.7% shares) and Schwab Strategic Tr (SCHH) (+31.3% shares), compared with its Q1 2026 filing.
What did Mason Street Advisors, LLC sell last quarter?
In Q2 2026, Mason Street Advisors, LLC sold all of Ishares Tr (VLUE), Ishares Tr (IEFA) (-10.7% shares) and Spdr Series Trust (SPMD) (-9.1% shares), compared with its Q1 2026 filing.
How has Mason Street Advisors, LLC's portfolio performed?
A portfolio copying Mason Street Advisors, LLC's 20 largest 13F holdings each quarter, from the day each filing was public, returned +11.1% a year over the last 3 years, against +20.4% for the S&P 500. Over 1 year: +11.7% against +20.1%. Over 5 years: +5.8% a year against +11.6%.
When is Mason Street Advisors, LLC's next 13F filing due?
13F filings are due 45 days after each quarter ends. Mason Street Advisors, LLC's filing for the quarter ending Sep 30, 2026 is due by Nov 14, 2026; this page updates the day after it is published.
How much money does Mason Street Advisors, LLC manage?
Mason Street Advisors, LLC reported $39.1B of regulatory assets under management on its latest SEC Form ADV. Its 13F, which covers only US-listed stocks and options, totals $1.1B.