Company · Ownership research

Boundless Bio, Inc. BOLD

CIK 0001782303 · CUSIP 10170A100

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

This page lists the top 20 of 36 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	FMR LLC CIK 315066 · View history	$2.96M 2,695,455 shares	0.00%	+11.43K(+0.40%)Added	SEC filing ↗ May 15, 2026	▾
02	CITADEL ADVISORS LLC CIK 1423053 · View history	$1.48M 1,342,131 shares	0.00%	-11.77K(-0.90%)Reduced	SEC filing ↗ May 15, 2026	▾
03	Sectoral Asset Management Inc CIK 1274413 · View history	$746.43K 678,574 shares	0.62%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2026	▾
04	Stonepine Capital Management, LLC CIK 1440771 · View history	$657.45K 597,682 shares	0.58%	-112.39K(-15.80%)Reduced	SEC filing ↗ May 14, 2026	▾
05	VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history	$656.91K 597,192 shares	0.00%	—	SEC filing ↗ May 15, 2026	▾
06	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$611.86K 556,233 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2026	▾
07	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$438.90K 399,000 shares	0.00%	+57.60K(+16.90%)Added	SEC filing ↗ May 14, 2026	▾
08	Alyeska Investment Group, L.P. CIK 1453072 · View history	$330.00K 300,000 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2026	▾
09	RBF Capital, LLC CIK 1134621 · Amended · View history	$220.00K 200,000 shares	0.01%	0(0.00%)Unchanged	SEC filing ↗ May 18, 2026	▾
10	Ensign Peak Advisors, Inc CIK 1454984 · Amended · View history	$206.25K 187,500 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ May 13, 2026	▾
11	Sio Capital Management, LLC CIK 1482416 · View history	$180.05K 163,679 shares	0.03%	0(0.00%)Unchanged	SEC filing ↗ May 14, 2026	▾
12	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$140.33K 127,576 shares	0.00%	+33.48K(+35.60%)Added	SEC filing ↗ May 15, 2026	▾
13	MILLENNIUM MANAGEMENT LLC CIK 1273087 · View history	$109.86K 99,875 shares	0.00%	-35.53K(-26.20%)Reduced	SEC filing ↗ May 15, 2026	▾
14	GSA CAPITAL PARTNERS LLP CIK 1362033 · View history	$107.00K 96,824 shares	0.01%	+34.35K(+55.00%)Added	SEC filing ↗ May 8, 2026	▾
15	LANDSCAPE CAPITAL MANAGEMENT, L.L.C. CIK 1536186 · View history	$94.37K 85,792 shares	0.01%	-41.83K(-32.80%)Reduced	SEC filing ↗ May 12, 2026	▾
16	BlackRock, Inc. CIK 2012383 · View history	$77.74K 70,675 shares	0.00%	+3.63K(+5.40%)Added	SEC filing ↗ May 13, 2026	▾
17	VANGUARD FIDUCIARY TRUST CO CIK 933478 · Amended · View history	$71.65K 65,136 shares	0.00%	—	SEC filing ↗ May 8, 2026	▾
18	BRIDGEWAY CAPITAL MANAGEMENT, LLC CIK 1107261 · View history	$55.55K 50,500 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2026	▾
19	Walleye Capital LLC CIK 1758720 · Amended · View history	$43.59K 39,624 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ May 13, 2026	▾
20	XTX Topco Ltd CIK 1828301 · View history	$38.14K 34,671 shares	0.00%	-4.91K(-12.40%)Reduced	SEC filing ↗ May 15, 2026	▾

Showing 20 / 36 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

Cancelled or null records excluded

Disclosed shares

8,485,823

Not deduplicated across managers

Disclosed value

$9.33M

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

Boundless Bio, Inc. · Q1 2026

Explore all 36 reporting institutions.

This page includes 20 of 36 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.