Stock ownership · SEC 13F · Q4 2024

IONIS PHARMACEUTICALS INC

Who owns IONIS PHARMACEUTICALS INC (CUSIP 462222AD2)? A look at the institutions behind it, how tightly they hold it, and the latest quarter's moves.

$14.3M
Reported value
2
Institutions
100%
Top-5 share

The verdict

As of Q4 2024, 2 institutions report $14.3M in IONIS PHARMACEUTICALS INC positions, ownership that is dominated by its top few institutional owners.

2
institutions hold it
$14.3M
reported 13F value
100%
held by top 5

Based on long positions reported to the SEC as of Q4 2024; 13F omits shorts, options and non-US holdings.

How 13F ownership is computed · All tracked stocks · Concentration rankings

SEC Form 13F-HR ownership desk

CUSIP 462222AD2 · Q4 2024 $14M reported

VALUE-TRACE · HOLDERS-FOCUS · CONC-DOM · PHOTO-UNK · ACTIVITY-QUIET · BOOK-SHORT

  • VALUE-TRACE $14.3M
  • HOLDERS-FOCUS 2 filers
  • CONC-DOM 100% top-5
  • PHOTO-UNK No peer
  • ACTIVITY-QUIET 0 new
  • BOOK-SHORT 1Q history

Read with: Ownership concentration guide - IONIS PHARMACEUTICALS INC's top-five holders account for 100% of reported value — read concentration before treating any single filer as a signal.

Top Institutional Holders

# Institution Shares Value Share of reported
1 SILVERBACK ASSET MANAGEMENT LLC 12,500,000 $12.1M 85.0%
2 Jefferies Financial Group Inc. (JEF) 2,213,000 $2.1M 15.0%

Investment Discretion

SEC Form 13F requires each institutional filer to report whether it exercises sole or shared discretion over a position. Among IONIS PHARMACEUTICALS INC's reported holders for Q4 2024, by reported value:

Sole discretion (SOLE)
85.0%
Shared-defined discretion (DFND)
15.0%

Frequently Asked Questions

How many institutions hold IONIS PHARMACEUTICALS INC?▼
IONIS PHARMACEUTICALS INC is held by 2 institutional investors per the latest SEC Form 13F filings as of Q4 2024.
What is the total institutional value of IONIS PHARMACEUTICALS INC?▼
Institutions report $14.3M of IONIS PHARMACEUTICALS INC as of Q4 2024.
How concentrated is ownership of IONIS PHARMACEUTICALS INC?▼
The top five institutional holders account for 100% of the reported institutional value in IONIS PHARMACEUTICALS INC, making ownership dominated by its top few institutional owners.
Who is the largest institutional holder of IONIS PHARMACEUTICALS INC?▼
SILVERBACK ASSET MANAGEMENT LLC is the largest reported holder of IONIS PHARMACEUTICALS INC with $12.1M across 12,500,000 shares as of Q4 2024.

Source: U.S. Securities and Exchange Commission (SEC) - EDGAR Form 13F-HR institutional holdings filings · Q4 2024 13F-HR discloses long US-listed equity positions of managers with $100M+ qualifying assets, filed within 45 days of period end. Short positions and most derivatives are not disclosed.

PlainFundData is rendered directly from SEC EDGAR Form 13F-HR institutional holdings filings, no number is typed in by an editor. Holder lists, concentration, and reported value on this page are aggregated live from those 13F-HR extracts. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-09-26.