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Caption Management’s Magnite MGNI Stock Holding History

Caption Management’s Portfolio MGNI Stock Details MGNI Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$17.8M Buy
1,500,000
+1,337,500
+823% +$17.9M 0.1% 208
2025
Q4 		$2.64M Sell
162,500
-237,500
-59% -$3.94M 0.02% 739
2025
Q3 		$8.71M Buy
+400,000
New +$9.45M 0.07% 314
2021
Q2 		– Sell
-10,700
Closed -$444K – 1477
2021
Q1 		$444K Buy
+10,700
New +$464K 0.01% 834

Other funds holding MGNI

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
Wellington Management Group
Wellington Management Group Boston, Massachusetts $535B AUM 26.23% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
Capital Research Global Investors
Capital Research Global Investors Los Angeles, California $645B AUM 30.41% 1-Year Est. Return
Boston Partners
Boston Partners Boston, Massachusetts $95.5B AUM 28.4% 1-Year Est. Return
American Century Companies
American Century Companies Kansas City, Missouri $194B AUM 35% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
Dimensional Fund Advisors
Dimensional Fund Advisors Austin, Texas $481B AUM 30.42% 1-Year Est. Return
N
Nuveen Charlotte, North Carolina $369B AUM 31.66% 1-Year Est. Return

Caption Management's MGNI Position: Q1 2026 in Review

Caption Management increased its Magnite (MGNI) stake by 2,400% in Q1 2026, buying an estimated $5.21M and bringing the position to 405,053 shares worth $4.81M. The position accounts for 0.03% of the portfolio, ranked #544.

Caption Management first reported a position in MGNI in Q4 2017 and has held it in 13 quarters since. The position peaked at $5.07M in Q4 2018. 296 funds tracked by Wall St. Rank hold MGNI as of Q1 2026.

  • Caption Management held 405,053 shares of Magnite worth $4.81M as of Q1 2026.
  • Caption Management bought 388,853 Magnite shares in Q1 2026, an estimated $5.21M.
  • Magnite made up 0.03% of Caption Management's portfolio in Q1 2026, its #544 holding.
  • Caption Management first reported a position in Magnite in Q4 2017 and has held it in 13 quarters since.
  • Caption Management's Magnite position peaked at $5.07M in Q4 2018.
  • 296 funds tracked by Wall St. Rank held Magnite as of Q1 2026.

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