Bain Capital Life Sciences Investors, LLC
CIK 1703031 · View on SEC EDGAR ↗
- Portfolio value
- $1.7B
- Positions
- 21
- As of
- June 30, 2026
Portfolio value QoQ: +51.7% 13F does not disclose cash
- Top 10 holdings weight
- 87.85%
- Top 25 holdings weight
- 100.00%
- Positions above 1%
- 15
- Effective number of positions
- 7.3
Based on 13F long-equity holdings only (cash, bonds, shorts not disclosed)
Turnover Q2 2026: 15.55% Est. buys $651,216,241 · sells $216,968,396
Median holding: 5.0 quarters Tracked Q4 2024–Q2 2026 · 61.8% still held
- New positions
- 2
- Increased
- 2
- Decreased
- 7
- Closed
- 1
On this page
- Performance vs S&P How this manager's 13F portfolio performed against the S&P 500.
- Sector breakdown How the portfolio splits across market sectors.
- Portfolio Every stock this institution reports holding, from its latest 13F.
- Biggest new bets Brand-new positions opened in the latest quarter.
- Top moves The biggest position increases and decreases this quarter.
- Exited positions Positions the manager fully sold out of last quarter.
Performance vs S&P 500
Annualized: +56.7% · S&P 500: +18.0%
Approximates a buy-and-hold portfolio built from quarterly SEC 13F snapshots. Excludes cash, short positions, options/derivatives, and non-13(f) securities — reflects the disclosed long-equity book only, not total fund AUM. SEC filing lag is up to 45 days; this is not a real-time-copyable timing.
Priceable coverage: 99.5% · Options excluded: 0.0%
Sector breakdown
Full portfolio 21 positions
| Type | Streak | 8Q trend | |||||
|---|---|---|---|---|---|---|---|
| Unknown issuer (CUSIP: 482931102) | $497,509,394 | 29.58% | 22,583,268 | Up ×1 | |||
| HTFL Heartflow, Inc. - Common Stock | $247,868,956 | 14.74% | 8,448,158 | $-6,334,728 | Down ×2 | ||
| NAMS NewAmsterdam Pharma Company N.V. - Ordinary Shares | $129,004,522 | 7.67% | 3,806,566 | $-104,878,656 | Down ×1 | ||
| SVRA Savara, Inc. - Common Stock | $108,419,826 | 6.45% | 17,600,621 | $12,320,435 | |||
| ALKS Alkermes plc - Ordinary Shares | $101,538,262 | 6.04% | 1,937,938 | $79,968,662 | Up ×1 | ||
| SLDB Solid Biosciences Inc. - Common Stock | $97,990,102 | 5.83% | 9,808,819 | $27,366,605 | |||
| PHVS Pharvaris N.V. - Ordinary Shares | $92,519,101 | 5.50% | 2,675,509 | $16,935,972 | |||
| OLMA Olema Pharmaceuticals, Inc. - Common Stock | $88,636,465 | 5.27% | 7,085,249 | $-22,789,514 | Down ×2 | ||
| Unknown issuer (CUSIP: 423494103) | $60,604,500 | 3.60% | 1,650,000 | Up ×1 | |||
| CABA Cabaletta Bio, Inc. - Common Stock | $53,620,894 | 3.19% | 17,241,445 | $27,589,428 | Up ×1 | ||
| XFOR X4 Pharmaceuticals, Inc. - Common Stock | $37,208,011 | 2.21% | 7,967,454 | $4,302,426 | |||
| DNTH Dianthus Therapeutics, Inc. - Common Stock | $35,333,576 | 2.10% | 362,470 | $4,915,094 | |||
| CCCC C4 Therapeutics, Inc. - Common Stock | $33,492,820 | 1.99% | 7,171,910 | $14,630,697 | |||
| KYTX Kyverna Therapeutics, Inc. - Common Stock | $25,705,350 | 1.53% | 2,885,000 | $-1,133,950 | Down ×1 | ||
| ANNX Annexon, Inc. - common stock | $25,339,444 | 1.51% | 4,437,731 | $-3,538,770 | Down ×2 | ||
| RPID Rapid Micro Biosystems, Inc. - Class A Common Stock | $14,591,789 | 0.87% | 8,434,560 | $-4,554,662 | |||
| IRON Disc Medicine, Inc. - Common Stock | $10,329,855 | 0.61% | 141,234 | $1,299,353 | |||
| AVIR Atea Pharmaceuticals, Inc. - common stock | $9,651,721 | 0.57% | 2,075,639 | $-3,048,511 | Down ×2 | ||
| Unknown issuer (CUSIP: 98422T209) | $6,361,322 | 0.38% | 664,021 | $776,905 | |||
| UPB Upstream Bio, Inc. - Common Stock | $4,158,567 | 0.25% | 600,949 | $-3,646,332 | Down ×3 | ||
| NAMSW NewAmsterdam Pharma Company N.V. - Warrant | $2,136,979 | 0.13% | 99,999 | $132,999 | |||
| No matches | |||||||
Biggest new bets
New positions opened this quarter, largest first.
| Security | Value | Shares | % of portfolio |
|---|---|---|---|
| Unknown issuer (CUSIP: 482931102) | $497,509,394 | 22,583,268 | 29.58% |
| Unknown issuer (CUSIP: 423494103) | $60,604,500 | 1,650,000 | 3.60% |
Top movers (QoQ)
| Security | Action | Shares Δ | Value Δ |
|---|---|---|---|
| NAMS | Trimmed | -3.5M | -$104.9M |
| ALKS | Bought more | +1.3M | +$80.0M |
| CABA | Bought more | +7.6M | +$27.6M |
| SLDB | Price move only | +0 | +$27.4M |
| OLMA | Trimmed | -388K | -$22.8M |
| PHVS | Price move only | +0 | +$16.9M |
| CCCC | Price move only | +0 | +$14.6M |
| SVRA | Price move only | +0 | +$12.3M |
| HTFL | Trimmed | -2.0M | -$6.3M |
| DNTH | Price move only | +0 | +$4.9M |
Exited positions
Includes corporate events (mergers, delistings) — not all exits are sells
Closed positions reflect 13F reporting changes; for index managers these are often mechanical (delisting, M&A, index rebalancing), not active decisions.
| Security | Quarter | Shares before | Value before | Price since exit |
|---|---|---|---|---|
| CDTX | Dec. 31, 2025 | 3,020,990 | $289,290,002 | No longer tracked |
| NUVL | Sept. 30, 2025 | 1,447,267 | $110,426,472 | No longer tracked |
| IRON | Sept. 30, 2025 | 583,500 | $30,902,160 | 18.5% |
| CNTA | June 30, 2026 | 635,000 | $25,222,200 | No longer tracked |
| MRSN | March 31, 2026 | 346,545 | $10,025,547 | No longer tracked |
| TNGX | March 31, 2026 | 653,493 | $5,789,948 | 14.9% |
| XLO | March 31, 2026 | 7,372,686 | $4,719,994 | 8.5% |
| XFORXXXX | June 30, 2025 | 16,915,784 | $3,998,891 | No longer tracked |
| IPSC | Dec. 31, 2025 | 3,538,609 | $1,762,227 | 107.0% |
| MRNS | March 31, 2025 | 2,693,380 | $1,441,228 | No longer tracked |
| IVVD | Sept. 30, 2025 | 1,799,595 | $1,286,710 | -20.0% |
| NAUT | June 30, 2025 | 1,072,421 | $923,354 | 26.7% |
| SYRS | March 31, 2025 | 2,750,151 | $631,985 | No longer tracked |