Magnetar Financial’s SiriusXM SIRI Stock Holding History

Magnetar Financial’s Portfolio SIRI Stock Details SIRI Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2014 Q2	–	Sell	-1,000,600	Closed	-$32M	–	231
2014 Q1	$32M	Buy	+1,000,600	New	+$35.4M	0.63%	48

Other funds holding SIRI

Berkshire Hathaway Omaha, Nebraska $299B AUM 27.55% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Dimensional Fund Advisors Austin, Texas $552B AUM 44.19% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

KCMH

Kontiki Capital Management (HK) Hong Kong $1.52B AUM 10.48% 1-Year Est. Return

State Street Boston, Massachusetts $3.37T AUM 44.26% 1-Year Est. Return

CCM

Check Capital Management Costa Mesa, California $7.52B AUM 15.3% 1-Year Est. Return

Boston Partners Boston, Massachusetts $113B AUM 38.87% 1-Year Est. Return

GCM

Gates Capital Management New York $4.16B AUM 21% 1-Year Est. Return

Magnetar Financial's SIRI Position: Q2 2026 in Review

Magnetar Financial sold out of SiriusXM (SIRI) in Q2 2026, closing a stake of 55,062 shares — an estimated $1.27M sold.

Magnetar Financial first reported a position in SIRI in Q1 2014 and held it in 10 quarters. The position peaked at $63.4M in Q1 2014. 600 funds tracked by Wall St. Rank hold SIRI as of Q2 2026.

Magnetar Financial reported no remaining SiriusXM position as of Q2 2026 after selling out during the quarter.
Magnetar Financial sold 55,062 SiriusXM shares in Q2 2026, an estimated $1.27M.
Magnetar Financial first reported a position in SiriusXM in Q1 2014 and held it in 10 quarters.
Magnetar Financial's SiriusXM position peaked at $63.4M in Q1 2014.
600 funds tracked by Wall St. Rank held SiriusXM as of Q2 2026.

Based on Magnetar Financial's 13F filing for Q2 2026, filed 14 Aug 2026.