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Castleark Management’s iShares MBS ETF MBB Stock Holding History

Castleark Management’s Portfolio MBB Stock Details MBB Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$19.4M Hold
204,235
– – 0.64% 33
2025
Q4 		$19.4M Buy
204,235
+7,330
+4% +$699K 0.57% 33
2025
Q3 		$18.7M Hold
196,905
– – 0.53% 31
2025
Q2 		$18.5M Hold
196,905
– – 0.56% 30
2025
Q1 		$18.5M Hold
196,905
– – 0.64% 29
2024
Q4 		$18.1M Buy
+196,905
New +$18.3M 0.63% 27

Other funds holding MBB

Bank of America
Bank of America Charlotte, North Carolina $1.37T AUM 24.88% 1-Year Est. Return
JP Morgan Chase
JP Morgan Chase New York $1.56T AUM 27.86% 1-Year Est. Return
Envestnet Asset Management
Envestnet Asset Management Chicago, Illinois $374B AUM 17.66% 1-Year Est. Return
LPL Financial
LPL Financial San Diego, California $377B AUM 19.32% 1-Year Est. Return
UBS Group
UBS Group Zurich, Switzerland $666B AUM 30.12% 1-Year Est. Return
TWIM
TIAA Wealth Investment Management New York $13.1B AUM
Ameriprise
Ameriprise Minneapolis, Minnesota $432B AUM 30.22% 1-Year Est. Return
Morgan Stanley
Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return
TCIIS
TIAA-CREF Individual & Institutional Services New York $26B AUM
Truist Financial
Truist Financial Charlotte, North Carolina $74.2B AUM 21.09% 1-Year Est. Return

Castleark Management's MBB Position: Q1 2026 in Review

Castleark Management held its iShares MBS ETF (MBB) position steady in Q1 2026 at 204,235 shares worth $19.4M. The position accounts for 0.64% of the portfolio, ranked #33.

Castleark Management first reported a position in MBB in Q4 2024 and has held it in 6 quarters since. The position peaked at $19.4M in Q4 2025. 1,019 funds tracked by Wall St. Rank hold MBB as of Q1 2026.

  • Castleark Management held 204,235 shares of iShares MBS ETF worth $19.4M as of Q1 2026.
  • Castleark Management left its iShares MBS ETF share count unchanged in Q1 2026.
  • iShares MBS ETF made up 0.64% of Castleark Management's portfolio in Q1 2026, its #33 holding.
  • Castleark Management first reported a position in iShares MBS ETF in Q4 2024 and has held it in 6 quarters since.
  • Castleark Management's iShares MBS ETF position peaked at $19.4M in Q4 2025.
  • 1,019 funds tracked by Wall St. Rank held iShares MBS ETF as of Q1 2026.

Based on Castleark Management's 13F filing for Q1 2026, filed 15 May 2026.