DIANTHUS THERAPEUTICS INC DNTH
COM · Common Stock · CUSIP 252828108
Biotechnology company
- SectorHealth care
- IndustryPharmaceutical Preparations
- HeadquartersNew York, NY
- Websitemagentatx.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 ($1.7m this quarter). Holder counts are more reliable. Shares outstanding: 44.5m as of 2026-03-04, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $83.43. Options: 6 managers hold calls ($19.7m notional), 8 hold puts ($22.3m).
Trends to Q1 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2023 | 31 |
| Q4 2023 | 40 |
| Q1 2024 | 77 |
| Q2 2024 | 75 |
| Q3 2024 | 92 |
| Q4 2024 | 97 |
| Q1 2025 | 100 |
| Q2 2025 | 104 |
| Q3 2025 | 140 |
| Q4 2025 | 166 |
| Q1 2026 | 241 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q2 2024 | 45 | 47 |
| Q3 2024 | 54 | 26 |
| Q4 2024 | 49 | 37 |
| Q1 2025 | 44 | 41 |
| Q2 2025 | 48 | 53 |
| Q3 2025 | 94 | 47 |
| Q4 2025 | 117 | 44 |
| Q1 2026 | 172 | 74 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q2 2025 | $2.7m | $571.8k | 0.21 |
| Q3 2025 | $15.6m | $14.3m | 0.92 |
| Q4 2025 | $914.9k | $3.0m | 3.31 |
| Q1 2026 | $19.7m | $22.3m | 1.14 |
Biggest buyers
| Avidity Partners Management LP | Added | +2.1m |
| FMR LLC | Added | +1.3m |
| T. Rowe Price Investment Management, Inc. | New | +1.3m |
| BlackRock, Inc. | Added | +1.3m |
| FRED ALGER MANAGEMENT, LLC | Added | +1.1m |
| DEERFIELD MANAGEMENT COMPANY, L.P. | New | +1.0m |
| RA CAPITAL MANAGEMENT, L.P. | Added | +1.0m |
| Cormorant Asset Management, LP | New | +950.0k |
| CITADEL ADVISORS LLC | Added | +541.5k |
| PRICE T ROWE ASSOCIATES INC /MD/ | Added | +530.9k |
Biggest sellers
| MARSHALL WACE, LLP | Reduced | -666.6k |
| Point72 Asset Management, L.P. | Reduced | -522.5k |
| Tri Locum Partners LP | Reduced | -476.9k |
| Octagon Capital Advisors LP | Reduced | -470.0k |
| MILLENNIUM MANAGEMENT LLC | Reduced | -405.3k |
| Bain Capital Life Sciences Investors, LLC | Reduced | -381.1k |
| BRAIDWELL LP | Reduced | -374.6k |
| GREAT POINT PARTNERS LLC | Sold out | -350.0k |
| Nantahala Capital Management, LLC | Reduced | -307.7k |
| BANK OF AMERICA CORP /DE/ | Reduced | -276.8k |
Biggest calls
| Caption Management, LLC | New | $8.7m103.9k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $5.5m65.5k shares |
| Affinity Asset Advisors, LLC | New | $4.2m50.0k shares |
| CITADEL ADVISORS LLC | New | $562.3k6.7k shares |
| JANE STREET GROUP, LLC | New | $478.3k5.7k shares |
| GROUP ONE TRADING LLC | Reduced | $209.8k2.5k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $11.9m141.7k shares |
| Caption Management, LLC | New | $4.2m50.0k shares |
| CITADEL ADVISORS LLC | Added | $2.7m31.8k shares |
| JANE STREET GROUP, LLC | New | $1.5m17.6k shares |
| PEAK6 LLC | New | $1.3m15.0k shares |
| GROUP ONE TRADING LLC | New | $537.1k6.4k shares |
| JPMORGAN CHASE & CO | New | $182.7k2.3k shares |
| SIMPLEX TRADING, LLC | Reduced | $109.1k1.3k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
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 +1.0 pts · filed 2025-11-05 | 15.0% |
| T. Rowe Price Investment Management, Inc. 13G · institution +5.0 pts · filed 2026-08-07 | 12.1% |
| BlackRock, Inc. 13G · institution +1.3 pts · filed 2026-07-28 | 6.4% |
| WELLINGTON MANAGEMENT GROUP LLP 13G · institution +1.1 pts · filed 2026-08-13 | 5.9% |
Fell to 5% or below in the last year: Sirenia Capital Management LP (3.1%, 2026-08-14), Point72 Asset Management, L.P. (1.2%, 2026-05-15), RA CAPITAL MANAGEMENT, L.P. (4.8%, 2026-05-15), Octagon Capital Advisors LP (3.6%, 2026-05-14), Fairmount Funds Management LLC (4.9%, 2025-11-25), Avidity Partners Management LP (4.9%, 2025-11-19), Deep Track Capital, LP (0.0%, 2025-11-14), BCLS Fund III Investments, LP (3.1%, 2025-11-14), Vestal Point Capital, LP (3.0%, 2025-11-14)
Insider purchases and sales in Q1 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.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q2 2024 | 0 | — | 0 | — | — |
| Q3 2024 | 0 | — | 0 | — | — |
| Q4 2024 | 0 | — | 0 | — | — |
| Q1 2025 | 0 | — | 0 | — | — |
| Q2 2025 | 0 | — | 0 | — | — |
| Q3 2025 | 0 | — | 1 | $700.0k | $700.0k |
| Q4 2025 | 0 | — | 2 | $8.3m | $8.3m |
| Q1 2026 | 0 | — | 5 | $28.0m | $28.0m |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-03-31 | Savitz Ryan EVP, CFO & CBO | Sold plan | $9.5m114.4k shares |
| 2026-03-31 | Soteropoulos Paula Director | Sold plan | $48.0k599 shares |
| 2026-03-24 | Soteropoulos Paula Director | Sold plan | $2.2m27.6k shares |
| 2026-03-12 | Garcia Marino CEO AND PRESIDENT, director | Sold plan | $10.0m122.9k shares |
| 2026-03-12 | CARR EDWARD CHIEF ACCOUNTING OFFICER | Sold plan | $3.6m43.7k shares |
| 2026-03-12 | Randhawa Simrat EVP, Head of R&D | Sold plan | $2.8m33.8k 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, Q1 2026
| Manager | Shares | Change |
|---|---|---|
| FMR LLC 0.03% of their portfolio | 7.8m $651.9m | Added +1.3m |
| Avidity Partners Management LP 38.62% of their portfolio | 4.2m $361.3m | Added +2.1m |
| BlackRock, Inc. 0.00% of their portfolio | 3.2m $266.5m | Added +1.3m |
| RA CAPITAL MANAGEMENT, L.P. 2.32% of their portfolio | 2.6m $219.2m | Added +1.0m |
| WELLINGTON MANAGEMENT GROUP LLP 0.04% of their portfolio | 2.6m $217.8m | Added +92.6k |
| Fairmount Funds Management LLC 15.38% of their portfolio | 2.5m $212.9m | Added +400.0k |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 2.0m $170.5m | First filing |
| Octagon Capital Advisors LP 18.08% of their portfolio | 1.9m $163.4m | Reduced -470.0k |
| TCG Crossover Management, LLC 4.03% of their portfolio | 1.7m $140.7m | Unchanged |
| CITADEL ADVISORS LLC 0.10% of their portfolio | 1.6m $135.2m | Added +541.5k |
| STATE STREET CORP 0.00% of their portfolio | 1.4m $117.4m | Reduced -108.7k |
| T. Rowe Price Investment Management, Inc. 0.07% of their portfolio | 1.3m $108.4m | New |
| Venrock Adviser, LLC 3.70% of their portfolio | 1.2m $99.0m | Added +180.0k |
| FRED ALGER MANAGEMENT, LLC 0.43% of their portfolio | 1.2m $97.5m | Added +1.1m |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.01% of their portfolio | 1.1m $96.3m | Added +530.9k |
| Polar Capital Holdings Plc 0.39% of their portfolio | 1.1m $90.3m | Added +71.3k |
| DEERFIELD MANAGEMENT COMPANY, L.P. 1.01% of their portfolio | 1.0m $85.6m | New |
| FRANKLIN RESOURCES INC 0.02% of their portfolio | 968.2k $81.2m | Added +505.4k |
| Cormorant Asset Management, LP 4.02% of their portfolio | 950.0k $79.7m | New |
| ALLIANCEBERNSTEIN L.P. 0.01% of their portfolio | 926.1k $38.2m | Added +91.7k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 916.2k $76.9m | Added +239.6k |
| BRAIDWELL LP 2.52% of their portfolio | 899.4k $75.5m | Reduced -374.6k |
| BAKER BROS. ADVISORS LP 0.41% of their portfolio | 852.2k $71.5m | Added +62.4k |
| FARALLON CAPITAL MANAGEMENT, L.L.C. 0.42% of their portfolio | 836.0k $70.2m | Not comparable |
| UBS Group AG 0.01% of their portfolio | 781.3k $65.6m | Added +174.7k |
| SILVERARC CAPITAL MANAGEMENT, LLC 6.47% of their portfolio | 654.7k $54.9m | Reduced -95.4k |
| Point72 Asset Management, L.P. 0.09% of their portfolio | 643.6k $54.0m | Reduced -522.5k |
| Catalio Capital Management, LP 9.82% of their portfolio | 560.3k $47.0m | Reduced -93.3k |
| GOLDMAN SACHS GROUP INC 0.01% of their portfolio | 548.0k $46.0m | Reduced -29.0k |
| JENNISON ASSOCIATES LLC 0.03% of their portfolio | 485.1k $40.7m | New |
| Balyasny Asset Management L.P. 0.08% of their portfolio | 474.1k $39.8m | New |
| Woodline Partners LP 0.14% of their portfolio | 433.5k $36.4m | Added +220.4k |
| SAMLYN CAPITAL, LLC 0.62% of their portfolio | 431.1k $36.2m | New |
| AMERIPRISE FINANCIAL INC 0.01% of their portfolio | 429.1k $36.0m | Added +274.0k |
| MPM BIOIMPACT LLC 2.75% of their portfolio | 424.0k $35.6m | New |
| Logos Global Management LP 1.73% of their portfolio | 400.0k $33.6m | Added +85.0k |
| Artisan Partners Limited Partnership 0.05% of their portfolio | 382.1k $32.1m | New |
| BARCLAYS PLC 0.01% of their portfolio | 379.6k $31.9m | Added +203.3k |
| Spruce Street Capital LP 7.53% of their portfolio | 373.3k $31.3m | Added +75.8k |
| Sio Capital Management, LLC 4.48% of their portfolio | 370.0k $31.1m | Reduced -104.5k |
| Bain Capital Life Sciences Investors, LLC 2.74% of their portfolio | 362.5k $30.4m | Reduced -381.1k |
| Vivo Capital, LLC 2.47% of their portfolio | 354.0k $29.7m | Unchanged |
| Affinity Asset Advisors, LLC 1.72% of their portfolio | 350.0k $29.4m | Added +235.0k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.00% of their portfolio | 349.4k $29.3m | First filing |
| MARSHALL WACE, LLP 0.03% of their portfolio | 341.9k $28.7m | Reduced -666.6k |
| DIMENSIONAL FUND ADVISORS LP 0.01% of their portfolio | 325.4k $27.3m | Added +114.8k |
| Driehaus Capital Management LLC 0.20% of their portfolio | 317.3k $26.6m | New |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 305.4k $25.6m | Added +54.6k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 303.8k $25.5m | Added +96.5k |
| LORD, ABBETT & CO. LLC 0.08% of their portfolio | 299.2k $25.1m | New |
| TANG CAPITAL MANAGEMENT LLC 1.13% of their portfolio | 264.7k $22.2m | Unchanged |
| MILLENNIUM MANAGEMENT LLC 0.02% of their portfolio | 262.0k $22.0m | Reduced -405.3k |
| VANGUARD FIDUCIARY TRUST CO 0.01% of their portfolio | 249.7k $21.0m | First filing |
| RTW INVESTMENTS, LP 0.21% of their portfolio | 248.1k $20.8m | New |
| Freestone Grove Partners LP 0.15% of their portfolio | 239.9k $20.1m | New |
| BNP PARIBAS FINANCIAL MARKETS 0.01% of their portfolio | 235.7k $19.8m | Reduced -240.0k |
| EVENTIDE ASSET MANAGEMENT, LLC 0.31% of their portfolio | 225.3k $18.9m | New |
| First Turn Management, LLC 2.07% of their portfolio | 220.9k $18.5m | New |
| Nuveen, LLC 0.00% of their portfolio | 217.5k $18.3m | Added +26.9k |
| Candriam S.C.A. 0.09% of their portfolio | 213.5k $17.9m | Reduced -97.6k |
| Ensign Peak Advisors, Inc 0.03% of their portfolio | 204.3k $17.1m | Added +69.9k |
| Jefferies Financial Group Inc. 0.21% of their portfolio | 202.4k $17.0m | New |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 188.8k $15.8m | Reduced -276.8k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 188.4k $15.8m | Added +113.3k |
| PFM Health Sciences, LP 1.52% of their portfolio | 172.1k $14.4m | Added +72.6k |
| STEMPOINT CAPITAL LP 1.39% of their portfolio | 171.0k $14.4m | Added +91.7k |
| Artia Global Partners LP 3.08% of their portfolio | 163.0k $13.7m | Reduced -42.1k |
| ADAGE CAPITAL PARTNERS GP, L.L.C. 0.02% of their portfolio | 160.0k $13.4m | New |
| Walleye Capital LLC 0.08% of their portfolio | 153.6k $12.9m | Reduced -52.2k |
| Integral Health Asset Management, LLC 0.67% of their portfolio | 150.0k $12.6m | Reduced -125.0k |
| D. E. Shaw & Co., Inc. 0.01% of their portfolio | 149.6k $12.6m | Reduced -5.1k |
| Tri Locum Partners LP 1.71% of their portfolio | 145.5k $12.2m | Reduced -476.9k |
| Invesco Ltd. 0.00% of their portfolio | 130.7k $11.0m | Added +29.3k |
| Russell Investments Group, Ltd. 0.01% of their portfolio | 129.1k $10.8m | Added +40.8k |
| Atika Capital Management LLC 1.71% of their portfolio | 128.8k $10.8m | Reduced -5.7k |
| TD Asset Management Inc 0.01% of their portfolio | 116.6k $9.8m | Added +84.8k |
| LMR Partners LLP 0.09% of their portfolio | 116.4k $9.8m | New |
| Hudson Bay Capital Management LP 0.06% of their portfolio | 109.2k $9.2m | New |
| Atom Investors LP 0.65% of their portfolio | 107.8k $9.0m | Reduced -74.1k |
| SummitTX Capital, L.P. 0.27% of their portfolio | 100.0k $8.4m | Added +12.1k |
| SEVEN GRAND MANAGERS, LLC 0.56% of their portfolio | 100.0k $8.4m | New |
| MORGAN STANLEY 0.00% of their portfolio | 97.5k $8.2m | Reduced -130.6k |
| Cinctive Capital Management LP 0.52% of their portfolio | 94.4k $7.9m | Added +48.5k |
| Patient Square Capital LP 1.40% of their portfolio | 93.9k $7.9m | Reduced -56.1k |
| SEI INVESTMENTS CO 0.01% of their portfolio | 92.2k $7.7m | Added +78.4k |
| ExodusPoint Capital Management, LP 0.07% of their portfolio | 85.5k $7.2m | Reduced -161.3k |
| Moody Aldrich Partners LLC 1.24% of their portfolio | 82.1k $6.9m | Added +40.8k |
| Rhenman & Partners Asset Management AB 0.85% of their portfolio | 81.6k $6.9m | Reduced -17.0k |
| Seven Fleet Capital Management LP 2.13% of their portfolio | 80.8k $6.8m | Added +66.2k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.01% of their portfolio | 80.0k $6.7m | Added +28.5k |
| AMERICAN CENTURY COMPANIES INC 0.00% of their portfolio | 79.1k $6.6m | Added +6.3k |
| Informed Momentum Co LLC 0.74% of their portfolio | 76.6k $6.4m | Reduced -8.0k |
| Schonfeld Strategic Advisors LLC 0.05% of their portfolio | 73.5k $6.2m | Reduced -109.2k |
| Swiss National Bank 0.00% of their portfolio | 69.0k $5.8m | Added +37.6k |
| Nantahala Capital Management, LLC 0.35% of their portfolio | 67.3k $5.6m | Reduced -307.7k |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio | 65.2k $5.5m | Added +39.6k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 60.4k $5.1m | Added +48.4k |
| Trexquant Investment LP 0.04% of their portfolio | 59.1k $5.0m | Added +53.9k |
| NEUBERGER BERMAN GROUP LLC 0.00% of their portfolio | 59.1k $5.0m | Reduced -28.7k |
| ADAR1 Capital Management, LLC 0.28% of their portfolio | 55.0k $4.6m | New |