Latest Period
Q2 2026
CUSIP: 10170A100
Latest Period
Q2 2026
Institutions Reporting
41
Shares (Excl. Options)
15,301,083
Price
$2.50
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Latest holder context comes from 41 institutions filings for Q2 2026.
Security key
10170A100
Latest holder period
Q2 2026
13F holders
41
13D/G owners
3
CIK / CUSIP context first
Broader feeds
Open recent reporting periods for CUSIP 10170A100:
13D/G owners
Large-stake holder rows connected to Schedule 13D/G evidence.
| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| FMR LLC | 12% | $3,086,625 | 2,684,022 | FMR LLC | 31 Dec 2025 | |||
| TANG CAPITAL MANAGEMENT LLC | 11% | $4,130,167 | 2,533,845 | TANG CAPITAL MANAGEMENT, LLC | 23 Jun 2026 | |||
| ADAR1 Capital Management, LLC | 8.8% | $4,920,540 | 1,968,216 | ADAR1 Capital Management, LLC | 30 Jun 2026 |
As of 30 Jun 2026, 41 institutional investors reported holding 15,301,083 shares of Boundless Bio, Inc. - Common Stock, par value $0.0001 per share (BOLD). This represents 68% of the company’s total 22,366,091 outstanding shares.
13F concentration
Largest 13F positions for this security by reported shares and value.
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| ARCH Venture Management, LLC | 12% | 2,694,095 | 0.61% | $6,735,238 | |
| FMR LLC | 12% | 2,581,055 | -4.2% | 0% | $6,452,638 |
| TANG CAPITAL MANAGEMENT LLC | 11% | 2,559,875 | 0.29% | $6,399,688 | |
| ADAR1 Capital Management, LLC | 8.8% | 1,968,216 | 0.23% | $4,920,540 | |
| Cormorant Asset Management, LP | 4.5% | 1,000,000 | 0.13% | $2,500,000 | |
| VANGUARD CAPITAL MANAGEMENT LLC | 2.7% | 614,923 | +3% | 0% | $1,537,308 |
| WELLINGTON MANAGEMENT GROUP LLP | 2.5% | 556,233 | 0% | 0% | $1,390,583 |
| MILLENNIUM MANAGEMENT LLC | 2.1% | 478,639 | +379% | 0% | $1,196,598 |
| RENAISSANCE TECHNOLOGIES LLC | 2.1% | 471,570 | +18% | 0% | $1,178,925 |
| Alyeska Investment Group, L.P. | 1.3% | 300,000 | 0% | 0% | $750,000 |
| Affinity Asset Advisors, LLC | 1.1% | 250,000 | 0.03% | $625,000 | |
| RBF Capital, LLC | 0.89% | 200,000 | 0% | 0.02% | $500,000 |
| Ensign Peak Advisors, Inc | 0.71% | 159,835 | -15% | 0% | $399,588 |
| Stonepine Capital Management, LLC | 0.69% | 154,595 | -74% | 0.3% | $386,488 |
| ACADIAN ASSET MANAGEMENT LLC | 0.66% | 146,757 | +1064% | 0% | $365,000 |
| CITADEL ADVISORS LLC | 0.65% | 145,049 | -89% | 0% | $362,623 |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | 0.57% | 128,000 | +153% | 0.01% | $320,000 |
| GEODE CAPITAL MANAGEMENT, LLC | 0.52% | 116,736 | -8.5% | 0% | $291,839 |
| HRT FINANCIAL LP | 0.52% | 116,288 | 0% | $290,000 | |
| BlackRock, Inc. | 0.4% | 88,495 | +25% | 0% | $221,239 |
| PRELUDE CAPITAL MANAGEMENT, LLC | 0.38% | 83,998 | 0.02% | $209,995 | |
| Rangeley Capital, LLC | 0.33% | 74,000 | 0.18% | $185,000 | |
| GSA CAPITAL PARTNERS LLP | 0.32% | 72,353 | -25% | 0.01% | $181,000 |
| VANGUARD FIDUCIARY TRUST CO | 0.29% | 65,136 | 0% | 0% | $162,840 |
| JANE STREET GROUP, LLC | 0.29% | 64,323 | 0% | $160,807 |
Quarter history
Holder count, reported shares/value, and median price by quarter.
| Period | 13F Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2026 Q2 | 15,301,083 | $38,250,210 | +$18,426,551 | $2.50 | 41 |
| 2026 Q1 | 8,485,823 | $9,333,021 | -$347,924 | $1.10 | 36 |
| 2025 Q4 | 8,780,936 | $10,536,019 | -$1,070,476 | $1.20 | 35 |
| 2025 Q3 | 9,621,325 | $11,833,310 | -$174,692 | $1.23 | 34 |
| 2025 Q2 | 9,787,223 | $9,883,853 | -$4,661,743 | $1.01 | 42 |
| 2025 Q1 | 13,012,498 | $19,647,091 | -$249,812 | $1.51 | 52 |
| 2024 Q4 | 12,962,230 | $37,589,408 | -$2,220,511 | $2.90 | 53 |
| 2024 Q3 | 13,275,578 | $46,065,519 | -$1,783,862 | $3.47 | 54 |
| 2024 Q2 | 13,842,210 | $53,440,888 | -$15,936,188 | $3.87 | 47 |
| 2024 Q1 | 14,582,563 | $208,788,470 | +$208,607,723 | $14.25 | 43 |