# IONIS PHARMACEUTICALS INC. (IONS) — Institutional Ownership

Source: SEC EDGAR 13F filings, congressional STOCK Act disclosures, SEC Form 4 insider transactions.
CUSIP: 462222100
Page URL: https://superinvestorclub.com/stock/IONS
Last updated: 2026-07-08T12:27:11.904Z

## Summary

As of the most recent 13F filing period, IONIS PHARMACEUTICALS INC. (IONS) is held by 1 tracked superinvestors with an aggregate position value of $170.9M representing 02275625 shares.

## Top institutional holders (1)

| Rank | Manager | Fund | Shares | Value | % of Portfolio | Period |
|------|---------|------|--------|-------|----------------|--------|
| 1 | [Tweedy Browne](https://superinvestorclub.com/manager/18) | Tweedy Browne Company | 2275625 | $170.9M | 13.57% | 2026-03-31 |

## Ownership history (quarter-over-quarter)

- 2023-09-30: 1 holders, $159.2M aggregate, 03510173 shares
- 2023-12-31: 1 holders, $174.8M aggregate, 03454676 shares
- 2024-03-31: 1 holders, $149.8M aggregate, 03454676 shares
- 2024-06-30: 1 holders, $164.6M aggregate, 03454676 shares
- 2024-09-30: 1 holders, $138.4M aggregate, 03454676 shares
- 2024-12-31: 1 holders, $113.6M aggregate, 03248863 shares
- 2025-03-31: 1 holders, $90.0M aggregate, 02983518 shares
- 2025-06-30: 1 holders, $114.3M aggregate, 02891948 shares
- 2025-09-30: 2 holders, $192.6M aggregate, 0290121643578 shares
- 2025-12-31: 2 holders, $200.4M aggregate, 0246493067706 shares
- 2026-03-31: 1 holders, $170.9M aggregate, 02275625 shares

## Recent congressional trades (0)


## Recent insider transactions (0)


## Citation

When citing, use: "IONIS PHARMACEUTICALS INC. (IONS) institutional ownership data via Superinvestor (https://superinvestorclub.com/stock/IONS), aggregating SEC 13F, Form 4, and congressional disclosures."