# Aktis Oncology, Inc. Common

Aktis Oncology, Inc. Common is a security (CUSIP 01021M104) tracked across SEC portfolio filings. 82 institutional managers reported $540.7M on Form 13F as of 2026-06-30; 16 registered fund positions totaling $77.0M via N-PORT as of 2026-05-31.

## Summary

- Issuer: Aktis Oncology, Inc.
- Class: Common
- CUSIP: 01021M104
- Asset category: EC
- 13F holders: 82
- 13F value: $540.7M
- 13F period: 2026-06-30
- N-PORT fund positions: 16
- N-PORT value: $77.0M
- N-PORT report: 2026-05-31

## Top institutional holders (Form 13F)

_Showing 15 of 82 managers by value._

| Manager | Location | Value | Shares |
| --- | --- | --- | --- |
| [MPM BIOIMPACT LLC](https://search.stillhousedata.com/firm/309865) | BOSTON, MA | $86.5M | 4,835,872 |
| [EcoR1 Capital, LLC](https://search.stillhousedata.com/firm/167121) | San Francisco, CA | $86.3M | 4,824,469 |
| Blue Owl Capital Holdings LP | New York, NY | $56.6M | 3,161,348 |
| WELLINGTON MANAGEMENT GROUP LLP | BOSTON, MA | $41.5M | 2,317,044 |
| BlackRock, Inc. | New York, NY | $37.8M | 2,112,127 |
| [RTW INVESTMENTS, LP](https://search.stillhousedata.com/firm/153232) | NEW YORK, NY | $28.5M | 1,592,043 |
| RA CAPITAL MANAGEMENT, L.P. | Boston, MA | $26.9M | 1,503,084 |
| JANUS HENDERSON GROUP PLC | LONDON, X0 | $26.0M | 1,454,267 |
| [BAKER BROS. ADVISORS LP](https://search.stillhousedata.com/firm/158149) | NEW YORK, NY | $17.8M | 996,351 |
| [Octagon Capital Advisors LP](https://search.stillhousedata.com/firm/306424) | NEW YORK, NY | $17.2M | 960,847 |
| Merck & Co., Inc. | RAHWAY, NJ | $17.0M | 952,844 |
| EVENTIDE ASSET MANAGEMENT, LLC | Boston, MA | $9.1M | 507,000 |
| [GEODE CAPITAL MANAGEMENT, LLC](https://search.stillhousedata.com/firm/115504) | BOSTON, MA | $8.8M | 491,936 |
| [Avidity Partners Management LP](https://search.stillhousedata.com/firm/304628) | DALLAS, TX | $8.4M | 468,566 |
| STATE STREET CORP | BOSTON, MA | $7.7M | 428,253 |

## Top fund holders (N-PORT)

_Showing 15 of 16 fund positions by value._

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [VANGUARD HEALTH CARE FUND](https://search.stillhousedata.com/fund/S000002922) | VANGUARD SPECIALIZED FUNDS | $37.9M | 10.29% |
| [T. Rowe Price Small-Cap Stock Fund, Inc.](https://search.stillhousedata.com/fund/S000002120) | T. ROWE PRICE SMALL-CAP STOCK FUND, INC. | $11.0M | 13.58% |
| [T. Rowe Price Health Sciences Fund, Inc.](https://search.stillhousedata.com/fund/S000002088) | T. ROWE PRICE HEALTH SCIENCES FUND, INC. | $6.0M | 5.48% |
| [T. Rowe Price Institutional Small-Cap Stock Fund](https://search.stillhousedata.com/fund/S000002094) | T. Rowe Price Equity Funds, Inc. | $5.7M | 13.24% |
| [VANGUARD EXTENDED MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002841) | VANGUARD INDEX FUNDS | $3.8M | 0.46% |
| [T. Rowe Price Small-Cap Value Fund, Inc.](https://search.stillhousedata.com/fund/S000002121) | T. ROWE PRICE SMALL-CAP VALUE FUND, INC. | $3.7M | 3.96% |
| [T. Rowe Price New Horizons Fund, Inc.](https://search.stillhousedata.com/fund/S000002106) | T. ROWE PRICE NEW HORIZONS FUND, INC. | $3.5M | 2.76% |
| [VANGUARD RUSSELL 2000 INDEX FUND](https://search.stillhousedata.com/fund/S000030003) | VANGUARD SCOTTSDALE FUNDS | $2.2M | 1.25% |
| BlackRock Health Sciences Term Trust | BlackRock Health Sciences Term Trust | $1.0M | 10.35% |
| [Master Small Cap Index Series](https://search.stillhousedata.com/fund/S000002716) | Quantitative Master Series LLC | $587K | 1.22% |
| [T. Rowe Price Spectrum Moderate Growth Allocation Fund](https://search.stillhousedata.com/fund/S000002138) | T. ROWE PRICE SPECTRUM FUNDS II, INC. | $457K | 1.06% |
| BlackRock Health Sciences Trust | BlackRock Health Sciences Trust | $416K | 7.80% |
| [T. Rowe Price Health Sciences Portfolio](https://search.stillhousedata.com/fund/S000002083) | T. ROWE PRICE EQUITY SERIES, INC. | $358K | 5.40% |
| [VANGUARD BALANCED INDEX FUND](https://search.stillhousedata.com/fund/S000002560) | VANGUARD VALLEY FORGE FUNDS | $183K | 0.03% |
| [VANGUARD INSTITUTIONAL TOTAL STOCK MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002855) | VANGUARD INSTITUTIONAL INDEX FUNDS | $144K | 0.05% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/01021M104.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.