Mariner Investment Group’s Costco COST Stock Holding History

Mariner Investment Group’s Portfolio COST Stock Details COST Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	–	Sell	-125,000	Closed	-$108M	–	117
2025 Q4	$108M	Buy	+125,000	New	+$113M	6.29%	4

Other funds holding COST

BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return

VCM

Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

Invesco Atlanta, Georgia $1.02T AUM 30.18% 1-Year Est. Return

VPM

Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM

Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return

Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return

Bank of America Charlotte, North Carolina $1.37T AUM 24.88% 1-Year Est. Return

DAM

Diamant Asset Management Ridgefield, Connecticut $137B AUM 18.02% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

Mariner Investment Group's COST Position: Q1 2026 in Review

Mariner Investment Group sold out of Costco (COST) in Q1 2026, closing a stake of 125,000 shares — an estimated $108M sold.

Mariner Investment Group first reported a position in COST in Q4 2025 and held it in 1 quarter. The position peaked at $108M in Q4 2025. 4,238 funds tracked by Wall St. Rank hold COST as of Q1 2026.

Mariner Investment Group reported no remaining Costco position as of Q1 2026 after selling out during the quarter.
Mariner Investment Group sold 125,000 Costco shares in Q1 2026, an estimated $108M.
Mariner Investment Group first reported a position in Costco in Q4 2025 and held it in 1 quarter.
Mariner Investment Group's Costco position peaked at $108M in Q4 2025.
4,238 funds tracked by Wall St. Rank held Costco as of Q1 2026.

Based on Mariner Investment Group's 13F filing for Q1 2026, filed 5 May 2026.