J.M. Arbour
IRM icon

J.M. Arbour’s Iron Mountain IRM Stock Holding History

J.M. Arbour’s Portfolio IRM Stock Details IRM Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q3 		$1.3M Buy
11,760
+53
+0.5% +$6.35K 1.04% 23
2026
Q2 		$1.48M Buy
11,707
+1,106
+10% +$136K 1.27% 18
2026
Q1 		$1.08M Sell
10,601
-259
-2% -$25.8K 1.04% 29
2025
Q4 		$901K Buy
+10,860
New +$1.02M 0.9% 34

Other funds holding IRM

BlackRock
BlackRock New York $6.79T AUM 37.06% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.21T AUM
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.76T AUM
State Street
State Street Boston, Massachusetts $3.44T AUM 36.12% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.92T AUM 36.1% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.32T AUM 44.66% 1-Year Est. Return
Morgan Stanley
Morgan Stanley New York $1.96T AUM 27.49% 1-Year Est. Return
Dimensional Fund Advisors
Dimensional Fund Advisors Austin, Texas $551B AUM 33.95% 1-Year Est. Return
Invesco
Invesco Atlanta, Georgia $1.27T AUM 50.62% 1-Year Est. Return
Principal Financial Group
Principal Financial Group Des Moines, Iowa $195B AUM 21.17% 1-Year Est. Return

J.M. Arbour's IRM Position: Q3 2026 in Review

J.M. Arbour increased its Iron Mountain (IRM) stake by 0.45% in Q3 2026, buying an estimated $6.35K and bringing the position to 11,760 shares worth $1.3M. The position accounts for 1.04% of the portfolio, ranked #23.

J.M. Arbour first reported a position in IRM in Q4 2025 and has held it in 4 quarters since. The position peaked at $1.48M in Q2 2026. 1,000 funds tracked by Wall St. Rank hold IRM as of Q3 2026.

  • J.M. Arbour held 11,760 shares of Iron Mountain worth $1.3M as of Q3 2026.
  • J.M. Arbour bought 53 Iron Mountain shares in Q3 2026, an estimated $6.35K.
  • Iron Mountain made up 1.04% of J.M. Arbour's portfolio in Q3 2026, its #23 holding.
  • J.M. Arbour first reported a position in Iron Mountain in Q4 2025 and has held it in 4 quarters since.
  • J.M. Arbour's Iron Mountain position peaked at $1.48M in Q2 2026.
  • 1,000 funds tracked by Wall St. Rank held Iron Mountain as of Q3 2026.

Based on J.M. Arbour's 13F filing for Q3 2026, filed 5 Nov 2026.