Rock Springs Capital Management LP
Portfolio value QoQ: +20.8% 13F does not disclose cash
Based on 13F long-equity holdings only (cash, bonds, shorts not disclosed)
Turnover Q2 2026: 13.68% Est. buys $256,139,663 · sells $263,128,657
Median holding: 4.0 quarters Tracked Q1 2025–Q2 2026 · 66.2% still held
Performance vs S&P 500
Annualized: +54.2% · S&P 500: +28.7%
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.
Sector breakdown
Full portfolio 104 positions
| Type | Streak | 8Q trend | |||||
|---|---|---|---|---|---|---|---|
| RVMD | $206,983,729 | 10.10% | 1,105,210 | $89,363,258 | Down ×2 | ||
| TVTX | $123,792,910 | 6.04% | 2,179,069 | $79,882,897 | Up ×1 | ||
| LLY | $118,383,741 | 5.78% | 98,700 | $27,602,442 | |||
| MDGL | $93,965,713 | 4.59% | 174,999 | $4,452,866 | Up ×3 | ||
| MIRM | $93,438,835 | 4.56% | 798,145 | $18,491,495 | Down ×1 | ||
| RYTM | $76,899,156 | 3.75% | 692,598 | $16,911,772 | Up ×1 | ||
| KYMR | $51,963,399 | 2.54% | 453,156 | $10,579,013 | Down ×1 | ||
| ARGX | $48,939,868 | 2.39% | 52,750 | $-22,989,757 | Down ×4 | ||
| Unknown issuer (CUSIP: K08588103) | $45,009,000 | 2.20% | 168,750 | Up ×1 | |||
| XENE | $41,280,627 | 2.01% | 683,907 | $-3,088,986 | Down ×4 | ||
| SRRK | $39,349,860 | 1.92% | 715,452 | $2,980,505 | Down ×1 | ||
| INSM | $38,612,433 | 1.88% | 362,150 | $-12,781,903 | Up ×1 | ||
| PEN | $36,548,063 | 1.78% | 115,750 | $-3,020,522 | Down ×1 | ||
| GPCR | $34,365,813 | 1.68% | 640,317 | $3,507,354 | Up ×1 | ||
| RARE | $32,316,678 | 1.58% | 967,855 | $6,783,384 | Down ×2 | ||
| IRTC | $32,074,868 | 1.57% | 269,650 | $1,183,133 | Up ×2 | ||
| ISRG | $30,406,613 | 1.48% | 76,460 | $-7,394,567 | Down ×1 | ||
| Unknown issuer (CUSIP: 00857U206) | $28,145,468 | 1.37% | 262,600 | $26,088,868 | Up ×1 | ||
| UNH | $26,496,413 | 1.29% | 63,750 | $12,155,143 | Up ×2 | ||
| CLDX | $26,015,223 | 1.27% | 699,146 | $5,388,659 | Up ×1 | ||
| ERAS | $25,687,388 | 1.25% | 1,402,150 | $7,833,260 | Up ×2 | ||
| NBIX | $24,395,441 | 1.19% | 144,750 | $4,575,158 | Down ×1 | ||
| ELVN | $23,579,719 | 1.15% | 464,625 | $-8,819,081 | Down ×1 | ||
| THC | $23,385,000 | 1.14% | 125,000 | $-203,750 | |||
| DXCM | $23,101,050 | 1.13% | 343,000 | $769,370 | Down ×1 | ||
| ACRS | $22,908,514 | 1.12% | 4,330,532 | $6,136,076 | Down ×1 | ||
| Unknown issuer (CUSIP: 60365F109) | $22,724,000 | 1.11% | 1,520,000 | $6,983,400 | Up ×1 | ||
| BSX | $22,556,380 | 1.10% | 528,500 | $-9,778,695 | Up ×5 | ||
| PHVS | $22,419,355 | 1.09% | 648,333 | $4,183,048 | Up ×2 | ||
| Unknown issuer (CUSIP: 05348Y105) | $21,823,261 | 1.07% | 662,918 | Up ×1 | |||
| Unknown issuer (CUSIP: 423494103) | $21,135,617 | 1.03% | 575,432 | Up ×1 | |||
| DYN | $20,925,240 | 1.02% | 942,154 | $3,299,290 | Down ×1 | ||
| ALNY | $20,093,753 | 0.98% | 66,750 | $-4,390,627 | Down ×1 | ||
| COGT | $19,965,988 | 0.97% | 515,917 | $-4,057,738 | Down ×3 | ||
| AGIO | $19,763,413 | 0.96% | 532,563 | $-7,272,271 | Down ×1 | ||
| NAMS | $19,749,194 | 0.96% | 582,744 | $901,898 | Down ×1 | ||
| VERA | $18,347,629 | 0.90% | 427,584 | $-1,911,596 | Down ×3 | ||
| TARS | $17,439,856 | 0.85% | 277,087 | $1,643,549 | Up ×1 | ||
| HTFL | $16,826,490 | 0.82% | 573,500 | $2,897,565 | Up ×3 | ||
| MBX | $16,461,634 | 0.80% | 298,218 | $7,865,819 | Up ×2 | ||
| CYTK | $16,014,016 | 0.78% | 187,980 | $13,024,075 | Up ×2 | ||
| BCAX | $15,892,641 | 0.78% | 535,286 | $6,164,541 | Up ×4 | ||
| Unknown issuer (CUSIP: 698955101) | $15,820,626 | 0.77% | 578,028 | Up ×1 | |||
| ZLAB | $15,479,433 | 0.76% | 814,707 | $154,794 | |||
| DHR | $14,533,624 | 0.71% | 76,300 | $2,873,224 | Up ×1 | ||
| TNGX | $14,271,784 | 0.70% | 456,551 | $6,177,522 | Up ×1 | ||
| EVH | $13,550,000 | 0.66% | 2,500,000 | $7,451,000 | Down ×1 | ||
| PTCT | $13,238,648 | 0.65% | 162,298 | $2,215,350 | Up ×2 | ||
| MLYS | $13,083,978 | 0.64% | 484,951 | $1,171,123 | Up ×5 | ||
| ZBIO | $12,742,714 | 0.62% | 502,077 | $2,927,109 | |||
| ARDX | $11,433,022 | 0.56% | 2,241,769 | $-2,340,821 | Down ×1 | ||
| INSP | $10,884,840 | 0.53% | 244,000 | $4,086,596 | Up ×5 | ||
| BBIO | $10,780,980 | 0.53% | 144,750 | $1,257,135 | Up ×3 | ||
| ALKS | $10,469,097 | 0.51% | 199,811 | $3,963,352 | Up ×3 | ||
| SMMT | $10,417,550 | 0.51% | 715,000 | $-3,044,050 | Up ×1 | ||
| AZTA | $10,284,560 | 0.50% | 403,000 | $-1,740,523 | Down ×1 | ||
| INDV | $10,072,865 | 0.49% | 245,500 | $3,976,865 | Up ×1 | ||
| SYK | $9,130,360 | 0.45% | 29,000 | $4,267,228 | Up ×1 | ||
| AMLX | $8,975,761 | 0.44% | 499,764 | $2,029,041 | |||
| CAI | $8,687,250 | 0.42% | 487,500 | $-1,379,190 | Down ×3 | ||
| OMDA | $8,187,350 | 0.40% | 373,000 | $1,386,980 | Down ×4 | ||
| CMPX | $7,719,595 | 0.38% | 3,524,929 | $-9,765,484 | Up ×1 | ||
| IMNM | $7,367,043 | 0.36% | 347,666 | $-236,412 | |||
| EDAP | $7,179,480 | 0.35% | 1,386,000 | $2,053,320 | Up ×3 | ||
| PHR | $7,171,101 | 0.35% | 696,900 | $2,139,749 | Up ×1 | ||
| OMER | $6,832,925 | 0.33% | 718,499 | Up ×1 | |||
| DFTX | $6,735,516 | 0.33% | 143,187 | Up ×1 | |||
| CORT | $6,260,400 | 0.31% | 72,000 | $4,234,822 | Up ×1 | ||
| JANX | $5,637,258 | 0.28% | 367,009 | $535,833 | |||
| Unknown issuer (CUSIP: 60705V103) | $5,603,880 | 0.27% | 418,200 | Up ×1 | |||
| RCUS | $5,549,400 | 0.27% | 180,000 | $1,661,400 | |||
| TMO | $5,013,600 | 0.24% | 10,000 | $98,300 | |||
| TRVI | $4,849,000 | 0.24% | 260,000 | Up ×1 | |||
| SION | $4,373,882 | 0.21% | 99,429 | $387,773 | |||
| CVS | $4,138,000 | 0.20% | 40,000 | $1,265,200 | |||
| EYPT | $3,839,822 | 0.19% | 268,519 | $504,676 | Up ×1 | ||
| OCUL | $3,768,091 | 0.18% | 383,716 | $518,016 | |||
| SYRE | $3,751,310 | 0.18% | 42,254 | Up ×1 | |||
| TLPH | $3,696,862 | 0.18% | 3,589,186 | $1,016,099 | |||
| ROIV | $3,574,390 | 0.17% | 101,000 | $887,490 | Up ×2 | ||
| PCVX | $3,502,333 | 0.17% | 60,250 | $1,205 | |||
| NGNE | $3,357,288 | 0.16% | 106,750 | $1,253,814 | Up ×1 | ||
| IPSC | $3,195,650 | 0.16% | 1,304,347 | $247,826 | |||
| ATEC | $3,114,000 | 0.15% | 360,000 | $-694,000 | Up ×2 | ||
| NVO | $3,044,190 | 0.15% | 63,500 | $-263,310 | Down ×1 | ||
| OLMA | $2,942,077 | 0.14% | 235,178 | $401,741 | Up ×2 | ||
| NGEN | $2,488,956 | 0.12% | 1,208,231 | Up ×1 | |||
| MDT | $2,417,307 | 0.12% | 30,900 | Up ×1 | |||
| TEVA | $1,998,920 | 0.10% | 59,000 | $628,460 | Up ×1 | ||
| DNTH | $1,981,378 | 0.10% | 20,326 | $-264,069 | Down ×1 | ||
| SGMT | $1,932,500 | 0.09% | 250,000 | ||||
| CAPR | $1,792,708 | 0.09% | 74,448 | Up ×1 | |||
| LENZ | $1,462,373 | 0.07% | 257,460 | $-893,386 | |||
| ALT | $1,433,254 | 0.07% | 471,465 | Up ×1 | |||
| Unknown issuer (CUSIP: 482931102) | $1,431,950 | 0.07% | 65,000 | Up ×1 | |||
| SGRY | $1,411,200 | 0.07% | 84,000 | $-1,068,160 | Down ×2 | ||
| AXSM | $1,346,235 | 0.07% | 5,500 | Up ×1 | |||
| ORKA | $1,146,894 | 0.06% | 12,051 | $944,661 | Up ×1 | ||
| VKTX | $994,755 | 0.05% | 25,500 | $-2,129,085 | Down ×1 | ||
| LEGN | $967,480 | 0.05% | 33,500 | $234,835 | Down ×1 | ||
| No matches | |||||||
Conviction holdings
Positions increased for 3+ consecutive quarters.
Share counts are as reported in 13F filings (not split-adjusted)
Biggest new bets
New positions opened this quarter, largest first.
| Security | Value | Shares | % of portfolio |
|---|---|---|---|
| Unknown issuer (CUSIP: K08588103) | $45,009,000 | 168,750 | 2.20% |
| Unknown issuer (CUSIP: 05348Y105) | $21,823,261 | 662,918 | 1.07% |
| Unknown issuer (CUSIP: 423494103) | $21,135,617 | 575,432 | 1.03% |
| Unknown issuer (CUSIP: 698955101) | $15,820,626 | 578,028 | 0.77% |
| OMER | $6,832,925 | 718,499 | 0.33% |
| DFTX | $6,735,516 | 143,187 | 0.33% |
| Unknown issuer (CUSIP: 60705V103) | $5,603,880 | 418,200 | 0.27% |
| TRVI | $4,849,000 | 260,000 | 0.24% |
| SYRE | $3,751,310 | 42,254 | 0.18% |
| NGEN | $2,488,956 | 1,208,231 | 0.12% |
| MDT | $2,417,307 | 30,900 | 0.12% |
| SGMT | $1,932,500 | 250,000 | 0.09% |
| CAPR | $1,792,708 | 74,448 | 0.09% |
| ALT | $1,433,254 | 471,465 | 0.07% |
| Unknown issuer (CUSIP: 482931102) | $1,431,950 | 65,000 | 0.07% |
Top movers (QoQ)
| Security | Action | Shares Δ | Value Δ |
|---|---|---|---|
| RVMD | Trimmed | -104K | +$89.4M |
| TVTX | Bought more | +701K | +$79.9M |
| LLY | Price move only | +0 | +$27.6M |
| ARGX | Trimmed | -46K | -$23.0M |
| MIRM | Trimmed | -13K | +$18.5M |
| RYTM | Bought more | +3K | +$16.9M |
| INSM | Bought more | +48K | -$12.8M |
| UNH | Bought more | +11K | +$12.2M |
| KYMR | Trimmed | -44K | +$10.6M |
| BSX | Bought more | +13K | -$9.8M |
2 positions hidden — reported move looks larger than the position itself (data completeness check)
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 |
|---|---|---|---|---|
| EXAS | March 31, 2026 | 601,800 | $61,118,808 | No longer tracked |
| MRUS | Dec. 31, 2025 | 597,051 | $56,212,352 | No longer tracked |
| CDTX | March 31, 2026 | 204,878 | $45,255,501 | No longer tracked |
| ASND | June 30, 2026 | 194,000 | $44,373,620 | -8.8% |
| AKRO | Dec. 31, 2025 | 626,526 | $29,747,454 | No longer tracked |
| BPMC | Sept. 30, 2025 | 185,500 | $23,777,390 | No longer tracked |
| ACLX | June 30, 2026 | 169,859 | $19,503,210 | No longer tracked |
| LEGN | June 30, 2025 | 512,932 | $17,403,783 | -45.7% |
| UNH | Sept. 30, 2025 | 50,500 | $15,754,485 | 21.1% |
| WRBY | June 30, 2025 | 835,000 | $15,222,050 | 18.1% |
| OSCR | Sept. 30, 2025 | 700,000 | $15,008,000 | 63.7% |
| CNTA | June 30, 2026 | 351,828 | $13,974,608 | No longer tracked |
| MREO | Dec. 31, 2025 | 4,570,649 | $9,415,537 | -32.4% |
| SLNO | June 30, 2026 | 257,253 | $8,612,830 | No longer tracked |
| REGN | June 30, 2026 | 10,100 | $7,803,664 | 29.1% |
| RAPT | March 31, 2026 | 213,731 | $7,239,069 | No longer tracked |
| NUVL | Sept. 30, 2025 | 93,328 | $7,120,926 | No longer tracked |
| APLS | June 30, 2026 | 162,750 | $6,547,433 | No longer tracked |
| TERN | June 30, 2026 | 113,748 | $5,996,795 | No longer tracked |
| CGEM | Sept. 30, 2025 | 668,233 | $5,031,794 | 142.3% |
| NVRO | June 30, 2025 | 800,494 | $4,674,885 | No longer tracked |
| AGL | March 31, 2026 | 6,500,000 | $4,476,550 | 1034.1% |
| MRSN | March 31, 2026 | 152,586 | $4,414,313 | No longer tracked |
| TBPH | March 31, 2026 | 208,771 | $3,906,105 | No longer tracked |
| XBI | June 30, 2026 | 30,000 | $3,831,900 | -5.5% |
| KMTS | June 30, 2025 | 145,000 | $3,613,400 | 73.5% |
| INZY | June 30, 2025 | 3,445,299 | $3,135,222 | No longer tracked |
| BEAM | June 30, 2025 | 150,020 | $2,929,891 | 41.4% |
| SGMT | June 30, 2025 | 787,808 | $2,568,254 | 25.7% |
| WST | Dec. 31, 2025 | 9,750 | $2,557,718 | 42.5% |
| EW | June 30, 2026 | 28,900 | $2,314,312 | -1.5% |
| ACHC | June 30, 2026 | 75,500 | $1,765,945 | 6.7% |
| KRRO | Dec. 31, 2025 | 35,719 | $1,710,583 | 49.6% |
| LUNG | Sept. 30, 2025 | 651,100 | $1,686,349 | 13.0% |
| BCRX | June 30, 2025 | 222,011 | $1,665,083 | -14.6% |
| CATX | Dec. 31, 2025 | 444,383 | $1,524,234 | No longer tracked |
| MGNX | June 30, 2025 | 1,145,214 | $1,454,422 | 86.0% |
| APLT | Dec. 31, 2025 | 2,075,991 | $1,255,767 | No longer tracked |
| IMVT | Dec. 31, 2025 | 72,965 | $1,176,196 | 11.8% |
| SRPT | Sept. 30, 2025 | 68,600 | $1,173,060 | -8.0% |
| JAZZ | June 30, 2026 | 5,750 | $1,087,038 | -11.2% |
| VIGL | June 30, 2025 | 471,958 | $840,085 | No longer tracked |
| PLRX | June 30, 2025 | 589,996 | $796,495 | -25.6% |
| SPRB | June 30, 2025 | 2,609,125 | $756,907 | |
| ADAPY | Sept. 30, 2025 | 2,483,468 | $595,287 | No longer tracked |
| GOSS | June 30, 2026 | 1,609,492 | $528,718 | -27.2% |
| CRL | Dec. 31, 2025 | 2,700 | $422,442 | 73.1% |
| ETNB | Sept. 30, 2025 | 40,000 | $392,800 | No longer tracked |
| NVAX | Dec. 31, 2025 | 45,000 | $390,150 | 44.3% |
| FOLD | June 30, 2026 | 21,062 | $304,557 | No longer tracked |
| PRTA | Dec. 31, 2025 | 25,398 | $247,884 | -14.1% |
| NUVBWS | March 31, 2026 | 134,028 | $44,229 | No longer tracked |
| CGEN | Dec. 31, 2025 | 13,430 | $19,742 | 26.8% |