Jane Street
MBSX

Jane Street’s Regan Fixed Rate MBS ETF MBSX Stock Holding History

Jane Street’s Portfolio MBSX Stock Details MBSX Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$327K Sell
11,599
-1,346
-10% -$36.1K ﹤0.01% 9042
2025
Q4 		$342K Sell
12,945
-2,625
-17% -$70.1K ﹤0.01% 8530
2025
Q3 		$429K Buy
15,570
+1,833
+13% +$48K ﹤0.01% 8184
2025
Q2 		$352K Buy
+13,737
New +$349K ﹤0.01% 7565

Other funds holding MBSX

CP
Castleview Partners Dallas, Texas $228M AUM 19.85% 1-Year Est. Return
AI
Auour Investments Woburn, Massachusetts $349M AUM 13.68% 1-Year Est. Return
CFA
Camarda Financial Advisors Fleming Island, Florida $190M AUM 48.71% 1-Year Est. Return
BWM
BlackDiamond Wealth Management New York $208M AUM 20.68% 1-Year Est. Return
Citadel Advisors
Citadel Advisors Miami, Florida $618B AUM 30.34% 1-Year Est. Return
DG
Diesslin Group Fort Worth, Texas $259M AUM
JP Morgan Chase
JP Morgan Chase New York $1.56T AUM 27.86% 1-Year Est. Return

Jane Street's MBSX Position: Q1 2026 in Review

Jane Street reduced its Regan Fixed Rate MBS ETF (MBSX) stake by 10% in Q1 2026, selling an estimated $36.1K and leaving 11,599 shares worth $327K. The position accounts for ﹤0.01% of the portfolio, ranked #9042.

Jane Street first reported a position in MBSX in Q2 2025 and has held it in 4 quarters since. The position peaked at $429K in Q3 2025. 8 funds tracked by Wall St. Rank hold MBSX as of Q1 2026.

  • Jane Street held 11,599 shares of Regan Fixed Rate MBS ETF worth $327K as of Q1 2026.
  • Jane Street sold 1,346 Regan Fixed Rate MBS ETF shares in Q1 2026, an estimated $36.1K.
  • Regan Fixed Rate MBS ETF made up ﹤0.01% of Jane Street's portfolio in Q1 2026, its #9042 holding.
  • Jane Street first reported a position in Regan Fixed Rate MBS ETF in Q2 2025 and has held it in 4 quarters since.
  • Jane Street's Regan Fixed Rate MBS ETF position peaked at $429K in Q3 2025.
  • 8 funds tracked by Wall St. Rank held Regan Fixed Rate MBS ETF as of Q1 2026.

Based on Jane Street's 13F filing for Q1 2026, filed 12 May 2026.