$IRON

$77.66 +$3.15 (4.23%) Close

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

Ownership

13F as of Q2 2026 · 38.4M shares outstanding

Who owns IRON?

By type of holder

Institutions 100.0% Insiders 0.0% Everyone else 0.0%

Concentration Top 10 holders own 70.6%

FMR LLC 12.8% · Len Blavatnik 7.7%

Institutional ownership

100.0%

0 pts vs last qtr

Institutional holders

214

+11 vs last qtr

Net shares bought

+861.5K

by institutions in Q2 2026

New / sold out

37 / 26

positions opened vs closed

How is ownership changing?

Institutions, last 8 quarters

Biggest buyers in Q2 2026

Vestal Point Capital, LP +850.0K
Jpmorgan Chase & Co +504.3K

Biggest sellers in Q2 2026

Orbimed Advisors LLC −710.0K
FMR LLC −692.4K

Who is planning to sell?

Notices of proposed sale, last 12 months

$84M

77 notices from 21 people

Shares covered

1.0M

2.63% of the company

Arranged in advance

25%

of the value is under a 10b5-1 plan

Under a 10b5-1 plan No plan

Largest proposed sellers

Atlas Venture Fund X, LP Shareholder $19.5M
John Quisel Director 10b5-1 $11.2M

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, FY2021–FY2025

+3918.1%

+151.77% a year

Each share's claim on the business

−97.5%

shrank without buying or selling a share

Spent on buybacks vs paid in stock

— vs $59.3M

over 5 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+ years0% 3–5 years54% 1–3 years29% Under 1 year17%

Quarterly turnover

9.7%

of institutional shares changed hands

Top 10 managers, median time held

3.5 years

Super Investors

Investment managers reporting IRON on Form 13F

Holder	Shares	% of company	Change vs last qtr	Held since	% of their book
F FMR LLC	4.9M	12.75%	−692.4K (−12.4%)	2022	0.0%
Shares held by quarter Peak holding5.6M (Q1'26) Change over 8 quarters+4.5M Share of the company12.750% FMR LLC's full portfolio →
B BlackRock, Inc.	2.5M	6.43%	+194.1K (+8.5%)	2022	0.0%
Shares held by quarter Peak holding2.5M (Q2'26) Change over 8 quarters+616.7K Share of the company6.430% BlackRock, Inc.'s full portfolio →

FMR LLC

4.9M

% of company

12.75%

Change vs last qtr

−692.4K (−12.4%)

Held since

2022

BlackRock, Inc.

2.5M

% of company

6.43%

Change vs last qtr

+194.1K (+8.5%)

Held since

2022

28 more super investors behind a free account

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

Institutional Funds

Mutual funds and ETFs reporting IRON on Form N-PORT; together they hold 40.1% of the company

Fund	Position value	Shares	% of company	% of the fund	As of
SA Strategic Advisers Fidelity U.S. Total Stock Fund Fidelity Rutland Square Trust II	$169M	2.2M	5.60%	0.06%	August 31, 2026
VT Vanguard Total Stock Market Index Fund Vanguard Index Funds	$71M	970.7K	2.53%	0.00%	June 30, 2026

Strategic Advisers Fidelity U.S. Total Stock Fund

Fidelity Rutland Square Trust II

Position value

$169M

% of company

5.60%

% of the fund

0.06%

As of

August 31, 2026

Vanguard Total Stock Market Index Fund

Vanguard Index Funds

Position value

$71M

% of company

2.53%

% of the fund

0.00%

As of

June 30, 2026

23 more funds behind a free account

See every fund holding Disc Medicine, 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
LB Len Blavatnik 5%+ holder 13D · 6.6%	2.9M	7.67%	—	—	—	—
This holder reports through Schedule 13D/G, not a quarterly 13F. Share of the company7.670% Disclosed stake13D · 6.6% View the 13D/G filing →
AI Access Industries Management, LLC 5%+ holder 13D · 6.6%	2.9M	7.67%	—	—	—	—
This holder reports through Schedule 13D/G, not a quarterly 13F. Share of the company7.670% Disclosed stake13D · 6.6% View the 13D/G filing →

Len Blavatnik

5%+ holder13D · 6.6%

2.9M

% of company

7.67%

Change vs last qtr

—

Held since

—

Access Industries Management, LLC

5%+ holder13D · 6.6%

2.9M

% of company

7.67%

Change vs last qtr

—

Held since

—

26 more holders behind a free account

See every insider and 5%+ holder of Disc Medicine, Inc..

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