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Mason Street Advisors, LLC

CIK 1167711 · latest 13F filed 12 August 2026 · Read the filing on EDGAR

Mason Street Advisors, LLC reported 15 US-listed holdings worth $1.11 billion in its 13F for the quarter ended 30 June 2026, filed 12 August 2026. Its largest: iShares Trust (27.2%), iShares Core S&P 500 ETF (13.9%) and SPDR Ser Trust (9.5%). Against the quarter before, it opened 1 position, added to 10, trimmed 3 and sold out of 1.

Reported holdings$1.11B+8.5% on Q1 2026
Positions15as many as Q1 2026
The largest ten90.6%of its reported holdings
Latest 13FQ2 2026filed 12 August 2026
Where the money is
OpenedAdded toHeldTrimmed
AGG27.2%IVV13.9%SPTL9.5%SPMD8.6%SPSM7.2%RSP5.5%IEFA5.5%RWR4.6%SCHH4.6%AVLV3.9%IQLT3.5%JPST2.3%DFIV2.0%BCI1.1%

The 14 largest of its 15 positions, each sized by its share of the reported holdings, coloured by the change in shares against Q1 2026.

Reported holdings, quarter by quarter
Q3 2024: $823.5 million in 12 positions$823MQ3 24Q4 2024: $772.6 million in 12 positions$773MQ4 24Q1 2025: $786.1 million in 13 positions$786MQ1 25Q2 2025: $854.5 million in 15 positions$855MQ2 25Q3 2025: $964.8 million in 15 positions$965MQ3 25Q4 2025: $1.02 billion in 15 positions$1.02BQ4 25Q1 2026: $1.02 billion in 15 positions$1.02BQ1 26Q2 2026: $1.11 billion in 15 positions$1.11BQ2 26

What the fund reported holding at each quarter's end; hover a bar for the number of positions

What it did on the quarter

Opened 1Added 10Held 1Trimmed 3Sold out 1
Opened: 1Added: 10Held: 1Trimmed: 3Sold out: 1

Its positions against its 13F for the quarter to 31 March 2026; a change under 0.1% of a position counts as held

Opened 1

  1. American Centy ETF Trust AVLV$43.3 million

Added to 10

  1. Schwab Strategic Trust SCHH+514,990 shares · +31%
  2. SPDR Ser Trust RWR+104,580 shares · +30%
  3. Invesco Exchange Traded FD T RSP+20,825 shares · +8%
  4. Abrdn Etfs BCI+184,160 shares · +52%
  5. SPDR Portfolio Small Cap ETF SPSM+52,825 shares · +4%
  6. iShares Core MSCI Emerging Mark IEMG+24,560 shares · +56%
  7. iShares Trust IQLT+23,736 shares · +3%
  8. Dimensional ETF Trust DFIV+10,970 shares · +3%

and 2 more in the table below

Trimmed 3

  1. SPDR Ser Trust SPMD-142,897 shares · -9%
  2. iShares Core MSCI Eafe ETF IEFA-76,244 shares · -11%
  3. iShares Core S&P 500 ETF IVV-5,196 shares · -2%

Sold out of 1

  1. iShares Trust VLUE$41.0 million last quarter

What it holds

CompanySharesValueOf its bookChange in shares
iShares Trust AGG3,050,830$302.0 million27.21%+1,567
iShares Core S&P 500 ETF IVV206,485$154.6 million13.93%-5,196
SPDR Ser Trust SPTL4,005,960$105.1 million9.47%+7,240
SPDR Ser Trust SPMD1,419,072$95.9 million8.64%-142,897
SPDR Portfolio Small Cap ETF SPSM1,379,248$79.5 million7.17%+52,825
Invesco Exchange Traded FD T RSP288,645$61.4 million5.53%+20,825
iShares Core MSCI Eafe ETF IEFA634,753$61.3 million5.52%-76,244
SPDR Ser Trust RWR453,255$51.2 million4.61%+104,580
Schwab Strategic Trust SCHH2,161,115$51.2 million4.61%+514,990
American Centy ETF Trust AVLV474,820$43.3 million3.90%new
iShares Trust IQLT792,666$39.3 million3.54%+23,736
JP Morgan Ultra Short Income Et JPST494,716$25.0 million2.25%+8,380
Dimensional ETF Trust DFIV414,285$22.4 million2.02%+10,970
Abrdn Etfs BCI540,495$12.1 million1.09%+184,160
iShares Core MSCI Emerging Mark IEMG68,080$5.6 million0.51%+24,560
Every US-listed position in the fund's 13F for the quarter ended 30 June 2026, by the value it reported.
Read moreChange is shares against its 13F for the quarter before; the 1 it sold out of are in the box above.