BAKER BROS. ADVISORS LP 13F: Quarter-over-Quarter Portfolio Changes
BAKER BROS. ADVISORS LP reported a disclosed portfolio value of approximately $20.0 billion in its latest SEC Form 13F-HR filing for Q2 2026, up 14.6% quarter on quarter. Over the quarter, the fund initiated 9 new positions, bought more shares in 16 holdings, trimmed 7 holdings, and exited 9 positions.
BAKER BROS. ADVISORS LP's top buy was a new stake in Celcuity INC. (SYN_15102KAA8) , equal to 0.3% of the disclosed portfolio. Its top sell was Abivax SA (ABVX) . The fund exited the position completely after it had accounted for 0.6% of the previous portfolio.
New PositionsQ2 2026
Securities disclosed for the first time in Q2 2026 that were not present in the prior 13F-HR filing.
| Company | Ticker | Initial Portfolio Weight | History |
|---|---|---|---|
| CELCUITY INC. | SYN_15102KAA8 | 0.3% | Holders → |
| FAETH THERAPEUTICS INC | SNSE | 0.2% | Holders → |
| CYTOKINETICS INC | CYTK | 0.1% | Holders → |
| INTELLIA THERAPEUTICS INC | NTLA | 0.1% | Holders → |
| PARABILIS MEDICINES INC | PBLS | 0.1% | Holders → |
| AVALYN PHARMACEUTICALS INC | AVLN | 0.1% | Holders → |
| TANGO THERAPEUTICS INC | TNGX | 0.1% | Holders → |
| AVALO THERAPEUTICS INC | AVTX | 0.1% | Holders → |
| IMMUNOME, INC. | IMNM | 0.0% | Holders → |
Top BuysQ2 2026
Showing the top 10 buys among 16 existing positions where the fund bought more shares in Q2 2026. Ranked by portfolio-weight impact, with the percentage of additional shares shown separately.
| Company | Ticker | Portfolio Weight Change | More Shares | History |
|---|---|---|---|---|
| VERASTEM INC | VSTM | +0.0% | +327.4% | Holders → |
| RELAY THERAPEUTICS INC | RLAY | +0.2% | +143.7% | Holders → |
| ARCUS BIOSCIENCES, INC. | RCUS | +0.1% | +103.3% | Holders → |
| CELLDEX THERAPEUTICS INC NEW | CLDX | +0.1% | +77.7% | Holders → |
| IDEAYA BIOSCIENCES INC | IDYA | +0.2% | +26.9% | Holders → |
| VIRIDIAN THERAPEUTICS INC | VRDN | +-0.0% | +20.9% | Holders → |
| REVOLUTION MEDICINES INC | RVMD | +5.4% | +19.8% | History → |
| INSMED INC | INSM | +-2.3% | +18.5% | History → |
| ABCELLERA BIOLOGICS INC. | ABCL | +0.7% | +9.0% | Holders → |
| DESIGN THERAPEUTICS INC | DSGN | +0.0% | +3.6% | Holders → |
Top SellsQ2 2026
The fund's top sells among positions it retained in Q2 2026. Ranked by portfolio-weight impact. Full exits are listed separately.
| Company | Ticker | Portfolio Weight Change | Shares Sold | History |
|---|---|---|---|---|
| EDGEWISE THERAPEUTICS INC | EWTX | -0.4% | 43.7% | Holders → |
| CERUS CORPORATION | CERS | -0.0% | 36.1% | Holders → |
| JADE BIOSCIENCES INC | JBIO | 0.0% | 25.0% | Holders → |
| IMMATICS N.V. | IMTX | -0.1% | 12.9% | Holders → |
| SUMMIT THERAPEUTICS INC | SMMT | -1.6% | 9.9% | Holders → |
| ROIVANT SCIENCES LTD | ROIV | 0.1% | 3.1% | Holders → |
| IMMUNOVANT INC | IMVT | 0.3% | 0.4% | Holders → |
Full ExitsQ2 2026
Positions present in the prior 13F-HR filing that no longer appear in Q2 2026.
| Company | Ticker | Last-Reported Portfolio Weight |
|---|---|---|
| ABIVAX SA | ABVX | 0.6% |
| CELCUITY INC. | CELC 2.75 08/01/31 | 0.4% |
| SPYRE THERAPEUTICS INC | SYRE | 0.3% |
| CENTESSA PHARMACEUTICALS PLC | CNTA | 0.2% |
| IMMUNOCORE HLDGS PLC | IMCR | 0.1% |
| CONTINEUM THERAPEUTICS, INC. | CTNM | 0.1% |
| ARGENX SE | ARGX | 0.1% |
| COMPASS PATHWAYS PLC | CMPS | 0.1% |
| PHARVARIS N V | PHVS | 0.1% |
Net Portfolio Value ChangeQ2 2026
- $17.4BPrior quarter
- $20.0BCurrent quarter
- +$2.5BNet delta
- +14.6%% change
Methodology & FAQ
How BAKER BROS. ADVISORS LP Quarterly Changes Are Computed
All deltas are sourced from sequential SEC Form 13F-HR filings for BAKER BROS. ADVISORS LP: each row joins the most recent filing against the immediately preceding quarterly filing for the same fund. Share-count changes reflect reported trading activity, while portfolio weights can also move because of market price changes. Portfolio weights are normalized to exclude listed options for comparability. A complete description, including how confidential treatment filings are handled, is documented in the Methodology.
What stocks did BAKER BROS. ADVISORS LP buy in Q2 2026?
In Q2 2026, BAKER BROS. ADVISORS LP initiated 9 new positions (CELCUITY INC. (SYN_15102KAA8), FAETH THERAPEUTICS INC (SNSE), CYTOKINETICS INC (CYTK), INTELLIA THERAPEUTICS INC (NTLA), PARABILIS MEDICINES INC (PBLS), AVALYN PHARMACEUTICALS INC (AVLN), TANGO THERAPEUTICS INC (TNGX), AVALO THERAPEUTICS INC (AVTX), IMMUNOME, INC. (IMNM)); bought more shares of VERASTEM INC (VSTM), RELAY THERAPEUTICS INC (RLAY), ARCUS BIOSCIENCES, INC. (RCUS), CELLDEX THERAPEUTICS INC NEW (CLDX), IDEAYA BIOSCIENCES INC (IDYA) (the largest 5 of 16 adds).
What stocks did BAKER BROS. ADVISORS LP sell in Q2 2026?
In Q2 2026, BAKER BROS. ADVISORS LP fully sold 9 positions (ABIVAX SA (ABVX), CELCUITY INC. (CELC 2.75 08/01/31), SPYRE THERAPEUTICS INC (SYRE), CENTESSA PHARMACEUTICALS PLC (CNTA), IMMUNOCORE HLDGS PLC (IMCR), CONTINEUM THERAPEUTICS, INC. (CTNM), ARGENX SE (ARGX), COMPASS PATHWAYS PLC (CMPS), PHARVARIS N V (PHVS)); reduced holdings in EDGEWISE THERAPEUTICS INC (EWTX), CERUS CORPORATION (CERS), JADE BIOSCIENCES INC (JBIO), IMMATICS N.V. (IMTX), SUMMIT THERAPEUTICS INC (SMMT) (the largest 5 of 7 reductions).
Which positions did BAKER BROS. ADVISORS LP initiate in Q2 2026?
BAKER BROS. ADVISORS LP established 9 new positions in Q2 2026: CELCUITY INC. (SYN_15102KAA8, 0.3%), FAETH THERAPEUTICS INC (SNSE, 0.2%), CYTOKINETICS INC (CYTK, 0.1%), INTELLIA THERAPEUTICS INC (NTLA, 0.1%), PARABILIS MEDICINES INC (PBLS, 0.1%), AVALYN PHARMACEUTICALS INC (AVLN, 0.1%), TANGO THERAPEUTICS INC (TNGX, 0.1%), AVALO THERAPEUTICS INC (AVTX, 0.1%), IMMUNOME, INC. (IMNM, 0.0%).
Which existing positions saw the largest allocation increases for BAKER BROS. ADVISORS LP in Q2 2026?
Of 16 existing positions with share-count increases in Q2 2026, the largest were: VERASTEM INC (VSTM, +0.0% weight, +327.4% shares), RELAY THERAPEUTICS INC (RLAY, +0.2% weight, +143.7% shares), ARCUS BIOSCIENCES, INC. (RCUS, +0.1% weight, +103.3% shares), CELLDEX THERAPEUTICS INC NEW (CLDX, +0.1% weight, +77.7% shares), IDEAYA BIOSCIENCES INC (IDYA, +0.2% weight, +26.9% shares), VIRIDIAN THERAPEUTICS INC (VRDN, +-0.0% weight, +20.9% shares), REVOLUTION MEDICINES INC (RVMD, +5.4% weight, +19.8% shares), INSMED INC (INSM, +-2.3% weight, +18.5% shares), ABCELLERA BIOLOGICS INC. (ABCL, +0.7% weight, +9.0% shares), DESIGN THERAPEUTICS INC (DSGN, +0.0% weight, +3.6% shares).
Which positions did BAKER BROS. ADVISORS LP fully exit in Q2 2026?
BAKER BROS. ADVISORS LP fully exited 9 positions in Q2 2026: ABIVAX SA (ABVX, last-reported weight 0.6%), CELCUITY INC. (CELC 2.75 08/01/31, last-reported weight 0.4%), SPYRE THERAPEUTICS INC (SYRE, last-reported weight 0.3%), CENTESSA PHARMACEUTICALS PLC (CNTA, last-reported weight 0.2%), IMMUNOCORE HLDGS PLC (IMCR, last-reported weight 0.1%), CONTINEUM THERAPEUTICS, INC. (CTNM, last-reported weight 0.1%), ARGENX SE (ARGX, last-reported weight 0.1%), COMPASS PATHWAYS PLC (CMPS, last-reported weight 0.1%), PHARVARIS N V (PHVS, last-reported weight 0.1%).
Which existing positions saw the largest allocation reductions for BAKER BROS. ADVISORS LP in Q2 2026?
Of 7 existing positions with share-count reductions in Q2 2026, the largest were: EDGEWISE THERAPEUTICS INC (EWTX, -0.4% weight, -43.7% shares), CERUS CORPORATION (CERS, -0.0% weight, -36.1% shares), JADE BIOSCIENCES INC (JBIO, 0.0% weight, -25.0% shares), IMMATICS N.V. (IMTX, -0.1% weight, -12.9% shares), SUMMIT THERAPEUTICS INC (SMMT, -1.6% weight, -9.9% shares), ROIVANT SCIENCES LTD (ROIV, 0.1% weight, -3.1% shares), IMMUNOVANT INC (IMVT, 0.3% weight, -0.4% shares).
Do quarter-over-quarter 13F allocation changes constitute explicit trading signals?
No. Quarter-over-quarter changes reflect a combination of active trading and market price movement. A weight increase can result from price appreciation alone, without the manager adding shares. Share-count delta is the cleaner indicator of explicit trading activity. All deltas on this page are sourced from sequential SEC Form 13F-HR filings.