$IRM

$113.08 +$3.12 (2.84%) Close

$IRM Overview Financial Statements SEC Filings Executives News Red Flags Capital Raising Ownership Insider Transactions Congressional Trades

Ownership

13F as of Q2 2026 · 297.7M shares outstanding

Who owns IRM?

By type of holder

Institutions 86.2% Insiders 0.1% Everyone else 13.7%

Concentration Top 10 holders own 46.3%

BlackRock, Inc. 11.3% · Vanguard Portfolio Management LLC 8.6%

Institutional ownership

86.2%

+1.2 pts vs last qtr

Institutional holders

1,156

+71 vs last qtr

Net shares bought

+3.5M

by institutions in Q2 2026

New / sold out

150 / 79

positions opened vs closed

How is ownership changing?

Institutions, last 8 quarters

Biggest buyers in Q2 2026

Norges Bank NEW +4.2M
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC +3.2M

Biggest sellers in Q2 2026

Cohen & Steers, Inc. −4.1M
Daiwa Securities Group Inc. −1.2M

Who is planning to sell?

Notices of proposed sale, last 12 months

$111M

32 notices from 8 people

Shares covered

1.0M

0.35% of the company

Arranged in advance

99%

of the value is under a 10b5-1 plan

Under a 10b5-1 plan No plan

Largest proposed sellers

Meaney William L Officer 10b5-1 $94M
Kidd Mark Officer 10b5-1 $6.51M

Every notice on Red Flags →

A Form 144 is notice of a planned sale, not the sale itself. What insiders actually sold is on Insider Transactions.

Is your stake being diluted?

Diluted share count, FY2016–FY2025

+20.4%

+2.09% a year

Each share's claim on the business

−17.0%

shrank without buying or selling a share

Spent on buybacks vs paid in stock

— vs $614M

over 10 fiscal years

Diluted shares, split-adjusted

Buybacks Stock-based comp

How patient are the owners?

Institutional shares by how long they've been held

5+ years80% 3–5 years8% 1–3 years7% Under 1 year6%

Quarterly turnover

6.8%

of institutional shares changed hands

Top 10 managers, median time held

5 years

Super Investors

Investment managers reporting IRM on Form 13F

Holder	Shares	% of company	Change vs last qtr	Held since	% of their book
B BlackRock, Inc.	33.6M	11.28%	+549.6K (+1.7%)	≤2021	0.1%
Shares held by quarter Peak holding35.2M (Q1'25) Change over 8 quarters+2.3M Share of the company11.280% BlackRock, Inc.'s full portfolio →
VP Vanguard Portfolio Management LLC	25.6M	8.59%	+553.4K (+2.2%)	≤2021	0.2%
Shares held by quarter Peak holding25.6M (Q2'26) Change over 8 quarters+25.6M Share of the company8.590% Vanguard Portfolio Management LLC's full portfolio →

BlackRock, Inc.

33.6M

% of company

11.28%

Change vs last qtr

+549.6K (+1.7%)

Held since

≤2021

Vanguard Portfolio Management LLC

25.6M

% of company

8.59%

Change vs last qtr

+553.4K (+2.2%)

Held since

≤2021

28 more super investors behind a free account

See every manager holding Iron Mountain Inc, how their position has changed, and how long they've held it.

Institutional Funds

Mutual funds and ETFs reporting IRM on Form N-PORT; together they hold 38.1% of the company

Fund	Position value	Shares	% of company	% of the fund	As of
VR Vanguard Real Estate Index Fund Vanguard Specialized Funds	$1.38B	11.3M	3.80%	1.89%	July 31, 2026
VT Vanguard Total Stock Market Index Fund Vanguard Index Funds	$1.13B	9.0M	3.01%	0.05%	June 30, 2026

Vanguard Real Estate Index Fund

Vanguard Specialized Funds

Position value

$1.38B

% of company

3.80%

% of the fund

1.89%

As of

July 31, 2026

Vanguard Total Stock Market Index Fund

Vanguard Index Funds

Position value

$1.13B

% of company

3.01%

% of the fund

0.05%

As of

June 30, 2026

23 more funds behind a free account

See every fund holding Iron Mountain Inc and how much of the fund the position is.

Insiders and 5%+ holders

From Forms 3/4/5 and Schedules 13D/G

Holder	Shares	% of company	Change vs last qtr	8 quarters	Held since	% of their book
BC Bailey Clark H Insider	242.5K	0.08%	—	—	—	—
Insider holdings come from Form 3/4/5 filings, which are not quarterly. Share of the company0.080% Bailey Clark H's insider activity →
BE Baker-Greene Edward Insider	8.2K	0.00%	—	—	—	—
Insider holdings come from Form 3/4/5 filings, which are not quarterly. Share of the company0.000% Baker-Greene Edward's insider activity →

Bailey Clark H

Insider

242.5K

% of company

0.08%

Change vs last qtr

—

Held since

—

Baker-Greene Edward

Insider

8.2K

% of company

0.00%

Change vs last qtr

—

Held since

—

Comments