Atlas Venture Life Science Advisors, LLC
CIK 1917529 · View on SEC EDGAR ↗
- Portfolio value
- $881.3M
- Positions
- 7
- As of
- June 30, 2026
Portfolio value QoQ: +11.6% 13F does not disclose cash
- Top 10 holdings weight
- 100.00%
- Top 25 holdings weight
- 100.00%
- Positions above 1%
- 7
- Effective number of positions
- 4.5
Based on 13F long-equity holdings only (cash, bonds, shorts not disclosed)
Turnover Q2 2026: 14.59% Est. buys $121,885,842 · sells $252,486,892
Median holding: 3.0 quarters Tracked Q4 2024–Q2 2026 · 41.2% still held
- New positions
- 1
- Increased
- 1
- Decreased
- 3
- Closed
- 2
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: +115.7% · S&P 500: +17.7%
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: 99.8% · Options excluded: 0.0%
Sector breakdown
Full portfolio 7 positions
| Type | Streak | 8Q trend | |||||
|---|---|---|---|---|---|---|---|
| KYMR Kymera Therapeutics, Inc. - Common Stock | $326,527,526 | 37.05% | 2,847,541 | $-54,774,760 | Down ×3 | ||
| DYN Dyne Therapeutics, Inc. - Common Stock | $151,030,199 | 17.14% | 6,800,099 | $-14,505,131 | Down ×1 | ||
| SION Sionna Therapeutics, Inc. - Common Stock | $131,776,532 | 14.95% | 2,995,602 | $11,682,848 | |||
| Unknown issuer (CUSIP: 482931102) | $113,923,342 | 12.93% | 5,171,282 | Up ×1 | |||
| IRON Disc Medicine, Inc. - Common Stock | $110,724,818 | 12.56% | 1,513,875 | $13,927,650 | |||
| QTTB Q32 Bio Inc. - Common Stock | $34,615,930 | 3.93% | 2,717,106 | $21,184,609 | Up ×1 | ||
| KRRO Korro Bio, Inc. - Common Stock | $12,690,811 | 1.44% | 962,884 | $-181,716 | Down ×1 | ||
| No matches | |||||||
Biggest new bets
New positions opened this quarter, largest first.
| Security | Value | Shares | % of portfolio |
|---|---|---|---|
| Unknown issuer (CUSIP: 482931102) | $113,923,342 | 5,171,282 | 12.93% |
Top movers (QoQ)
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 |
|---|---|---|---|---|
| DAWN | March 31, 2026 | 6,412,560 | $59,765,059 | No longer tracked |
| THRD | Sept. 30, 2025 | 10,402,286 | $56,484,413 | No longer tracked |
| VIGL | Sept. 30, 2025 | 5,836,874 | $46,403,148 | No longer tracked |
| IKNA | Sept. 30, 2025 | 5,018,178 | $6,724,359 | No longer tracked |
| GBIO | March 31, 2026 | 827,946 | $4,702,732 | No longer tracked |
| AVTE | June 30, 2025 | 1,799,232 | $4,516,072 | No longer tracked |
| TECX | March 31, 2025 | 78,447 | $3,621,898 | 113.0% |
| IMA | Dec. 31, 2025 | 377,814 | $3,079,184 | -15.6% |
| SPRO | June 30, 2025 | 305,255 | $219,784 | -57.9% |