BOUNDLESS BIO INC BOLD
COM · Common Stock · CUSIP 10170A100
Company in San Diego, United States
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersLa Jolla, CA
- Founded2018
- Websiteboundlessbio.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once. Holder counts are more reliable. Implied quarter-end price ≈ $2.50.
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q1 2024 | 44 |
| Q2 2024 | 48 |
| Q3 2024 | 56 |
| Q4 2024 | 56 |
| Q1 2025 | 55 |
| Q2 2025 | 45 |
| Q3 2025 | 35 |
| Q4 2025 | 36 |
| Q1 2026 | 36 |
| Q2 2026 | 40 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 21 | 20 |
| Q4 2024 | 36 | 13 |
| Q1 2025 | 19 | 21 |
| Q2 2025 | 18 | 40 |
| Q3 2025 | 8 | 25 |
| Q4 2025 | 16 | 14 |
| Q1 2026 | 10 | 17 |
| Q2 2026 | 23 | 17 |
Biggest buyers
| ARCH Venture Management, LLC | New | +2.7m |
| TANG CAPITAL MANAGEMENT LLC | New | +2.6m |
| ADAR1 Capital Management, LLC | New | +2.0m |
| Cormorant Asset Management, LP | New | +1.0m |
| MILLENNIUM MANAGEMENT LLC | Added | +378.8k |
| Affinity Asset Advisors, LLC | New | +250.0k |
| ACADIAN ASSET MANAGEMENT LLC | Added | +134.1k |
| HRT FINANCIAL LP | New | +116.3k |
| PRELUDE CAPITAL MANAGEMENT, LLC | New | +84.0k |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | Added | +77.5k |
Biggest sellers
| CITADEL ADVISORS LLC | Reduced | -1.2m |
| SECTORAL ASSET MANAGEMENT INC | Sold out | -678.6k |
| Stonepine Capital Management, LLC | Reduced | -443.1k |
| Sio Capital Management, LLC | Sold out | -163.7k |
| FMR LLC | Reduced | -114.4k |
| LANDSCAPE CAPITAL MANAGEMENT, L.L.C. | Sold out | -85.8k |
| Walleye Capital LLC | Sold out | -39.6k |
| Ensign Peak Advisors, Inc | Reduced | -27.7k |
| GSA CAPITAL PARTNERS LLP | Reduced | -24.5k |
| Squarepoint Ops LLC | Sold out | -16.4k |
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| FMR LLC 13G · institution filed 2026-02-05 | 12.0% |
| TANG CAPITAL MANAGEMENT LLC 13G · passive investor new · filed 2026-06-29 | 11.3% |
| Hornby Zachary 13G · passive investor new · filed 2026-08-27 | 9.8% |
| ADAR1 Capital Management, LLC 13G · institution new · filed 2026-08-14 | 8.8% |
Fell to 5% or below in the last year: CITADEL ADVISORS LLC (0.6%, 2026-08-14), Nextech VI GP S.A.R.L. (0.0%, 2026-02-17)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-08-26 | TANG KEVIN +1 10% owner · See Footnote | Sold | $54.4k18.3k shares |
| 2026-07-21 | TANG KEVIN +1 10% owner · See Footnote | Bought | $7.3k3.0k shares |
| 2026-07-20 | TANG KEVIN +1 10% owner · See Footnote | Bought | $4.0k1.6k shares |
| 2026-07-17 | TANG KEVIN +1 10% owner · See Footnote | Bought | $647265 shares |
| 2026-07-16 | TANG KEVIN +1 10% owner · See Footnote | Bought | $45.1k18.5k shares |
| 2026-07-15 | TANG KEVIN +1 10% owner · See Footnote | Bought | $3.9k1.6k shares |
| 2026-07-14 | TANG KEVIN +1 10% owner · See Footnote | Bought | $106.6k43.9k shares |
| 2026-07-13 | TANG KEVIN +1 10% owner · See Footnote | Bought | $116.7k48.2k shares |
| 2026-07-10 | TANG KEVIN +1 10% owner · See Footnote | Bought | $105.4k43.4k shares |
| 2026-07-09 | TANG KEVIN +1 10% owner · See Footnote | Bought | $177 shares |
| 2026-07-08 | TANG KEVIN +1 10% owner · By LP | Bought | $35.3k14.3k shares |
| 2026-07-07 | TANG KEVIN +1 10% owner · By LP | Bought | $39.2k15.8k shares |
| 2026-07-06 | TANG KEVIN +1 10% owner · By LP | Bought | $67.4k27.1k shares |
| 2026-07-02 | TANG KEVIN +1 10% owner · By LP | Bought | $24.5k9.8k shares |
| 2026-07-01 | TANG KEVIN +1 10% owner · By LP | Bought | $178.3k71.6k shares |
| 2026-07-01 | CRANDELL KEITH +4 10% owner · See footnote | Sold | $39.8k16.0k shares |
| 2026-07-01 | ARCH Venture Fund IX, L.P. +7 10% owner · See footnote | Sold | $39.8k16.0k shares |
| 2026-06-30 | TANG KEVIN +1 10% owner · By LP | Bought | $66.1k26.0k shares |
| 2026-06-29 | TANG KEVIN +1 10% owner · By LP | Bought | $160.0k64.8k shares |
| 2026-06-26 | TANG KEVIN +1 10% owner · By LP | Bought | $191.7k75.2k shares |
| 2026-06-25 | TANG KEVIN +1 10% owner · By LP | Bought | $363.1k146.4k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| ARCH Venture Management, LLC 0.61% of their portfolio | 2.7m $6.7m | New |
| FMR LLC 0.00% of their portfolio | 2.6m $6.5m | Reduced -114.4k |
| TANG CAPITAL MANAGEMENT LLC 0.29% of their portfolio | 2.6m $6.4m | New |
| ADAR1 Capital Management, LLC 0.23% of their portfolio | 2.0m $4.9m | New |
| Cormorant Asset Management, LP 0.13% of their portfolio | 1.0m $2.5m | New |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 614.9k $1.5m | Added +17.7k |
| WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio | 556.2k $1.4m | Unchanged |
| MILLENNIUM MANAGEMENT LLC 0.00% of their portfolio | 478.6k $1.2m | Added +378.8k |
| RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio | 471.6k $1.2m | Added +72.6k |
| Alyeska Investment Group, L.P. 0.00% of their portfolio | 300.0k $750.0k | Unchanged |
| Affinity Asset Advisors, LLC 0.03% of their portfolio | 250.0k $625.0k | New |
| RBF Capital, LLC 0.02% of their portfolio | 200.0k $500.0k | Unchanged |
| Ensign Peak Advisors, Inc 0.00% of their portfolio | 159.8k $399.6k | Reduced -27.7k |
| Stonepine Capital Management, LLC 0.29% of their portfolio | 154.6k $386.5k | Reduced -443.1k |
| ACADIAN ASSET MANAGEMENT LLC 0.00% of their portfolio | 146.8k $365.0k | Added +134.1k |
| CITADEL ADVISORS LLC 0.00% of their portfolio | 145.0k $362.6k | Reduced -1.2m |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC 0.01% of their portfolio | 128.0k $320.0k | Added +77.5k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 116.7k $291.8k | Reduced -10.8k |
| HRT FINANCIAL LP 0.00% of their portfolio | 116.3k $290.0k | New |
| BlackRock, Inc. 0.00% of their portfolio | 88.5k $221.2k | Added +17.8k |
| PRELUDE CAPITAL MANAGEMENT, LLC 0.02% of their portfolio | 84.0k $210.0k | New |
| Rangeley Capital, LLC 0.17% of their portfolio | 74.0k $185.0k | New |
| GSA CAPITAL PARTNERS LLP 0.01% of their portfolio | 72.4k $181.0k | Reduced -24.5k |
| VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio | 65.1k $162.8k | Unchanged |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 64.3k $160.8k | New |
| SUPERSTRING CAPITAL MANAGEMENT LP 0.09% of their portfolio | 55.4k $138.4k | New |
| NORTHERN TRUST CORP 0.00% of their portfolio | 34.8k $87.1k | New |
| XTX Topco Ltd 0.00% of their portfolio | 33.4k $83.4k | Reduced -1.3k |
| Qube Research & Technologies Ltd 0.00% of their portfolio | 20.2k $50.5k | Added +2.7k |
| China Universal Asset Management Co., Ltd. 0.00% of their portfolio | 16.9k $42.2k | New |
| STATE STREET CORP 0.00% of their portfolio | 16.0k $39.9k | Unchanged |
| MORGAN STANLEY 0.00% of their portfolio | 13.0k $32.5k | Unchanged |
| Caitong International Asset Management Co., Ltd 0.00% of their portfolio | 10.4k $26.1k | Added +10.4k |
| Pure Financial Advisors, LLC 0.00% of their portfolio | 10.1k $25.2k | Unchanged |
| Tower Research Capital LLC (TRC) 0.00% of their portfolio | 348 $870 | Reduced -2.0k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 179 $439 | Added +10 |
| BNP PARIBAS FINANCIAL MARKETS 0.00% of their portfolio | 176 $440 | Reduced -2 |
| Financial Management Professionals, Inc. 0.00% of their portfolio | 2 $5 | New |
| UBS Group AG 0.00% of their portfolio | 2 $5 | Unchanged |
| SBI Securities Co., Ltd. 0.00% of their portfolio | 2 $5 | Added +1 |