513 institutional investment managers reported IONS positions in their Form 13F filings for Q2 2026, holding 179,752,611 shares worth $14.3B in total. FMR LLC reported the largest position.

Are funds buying or selling IONS?

In Q2 2026, 63 managers opened new IONS positions, 196 added, 159 trimmed and 46 sold out. Managers that filed in both quarters added a net 6,852,579 shares.

How current is this IONS institutional ownership data?

It covers holdings as of the end of Q2 2026. Managers have 45 days after the quarter ends to file Form 13F (by August 14, 2026 for Q2 2026), so positions may have changed since.

Funds · IONS

Who owns IONS?

Institutional ownership of Ionis Pharmaceuticals Inc. from Form 13F, Q2 2026

513 institutional managers reported holding Ionis Pharmaceuticals Inc. (IONS) in Form 13F filings for Q2 2026, with 179,752,611 shares worth $14.3B. The largest reported holder was FMR LLC. Managers that filed both quarters added a net 6,852,579 shares (+4.0%). 63 opened new positions and 46 sold out.

Funds holding: 513
Value held: $14.3B
New / sold out: 63 / 46
Net shares, same filers: +4.0%

Holdings as of June 30, 2026, the end of Q2 2026. Managers have 45 days after a quarter ends to file Form 13F (by August 14, 2026 for Q2 2026), so positions may have changed since.

Largest holders of IONS

Fund	Value	Share of 13F holdings	Shares	Move
FMR LLC	$2.0B	13.7%	24,631,956	Added
Capital World Investors	$1.7B	12.1%	21,669,226	Added
BlackRock, Inc.	$849M	6.0%	10,704,660	Added
Vanguard Portfolio Management LLC	$623M	4.4%	7,859,529	Added
Wellington Management Group LLP	$607M	4.3%	7,651,415	Added
Vanguard Capital Management LLC	$572M	4.0%	7,211,497	Added
Two Sigma Investments, LP	$496M	3.5%	6,252,342	Added
Royal Bank of Canada	$490M	3.4%	6,182,479	Added
State Street Corp	$344M	2.4%	4,334,848	Added
T. Rowe Price Investment Management, Inc.	$314M	2.2%	3,959,372	Trimmed
Geode Capital Management, LLC	$295M	2.0%	3,584,024	Trimmed
Price T Rowe Associates Inc	$253M	1.8%	3,184,500	Added
JPMorgan Chase & Co	$216M	1.5%	2,671,717	Added
Artisan Partners Limited Partnership	$209M	1.5%	2,640,024	Added
Tweedy, Browne Co LLC	$181M	1.3%	2,280,311	Added
Deep Track Capital, LP	$174M	1.2%	2,200,000	Added
Goldman Sachs Group Inc	$167M	1.2%	2,109,945	Added
Baker Bros. Advisors LP	$162M	1.1%	2,047,727	Unchanged
Deerfield Management Company, L.p.	$157M	1.1%	1,979,669	Unchanged
American Century Companies Inc	$154M	1.1%	1,947,076	Added
Franklin Resources Inc	$129M	0.9%	1,623,377	Added
Charles Schwab Investment Management Inc	$127M	0.9%	1,605,054	Added
Barclays PLC	$127M	0.9%	1,603,136	Added
Pictet Asset Management Holding SA	$127M	0.9%	1,596,998	Added
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC	$115M	0.8%	1,454,672	Trimmed

Share of 13F holdings is each fund's shares as a share of the 179,752,611 IONS shares all 13F filers reported, not of shares outstanding.

Biggest buyers in Q2 2026

Royal Bank of Canada Added+$189M
Barclays PLC Added+$104M
Wellington Management Group LLP Added+$99.9M
Alyeska Investment Group, L.P. Added+$74.9M
Capital International Investors New+$65.3M
Polar Capital Holdings Plc Added+$49.5M
Artisan Partners Limited Partnership Added+$46.1M
Nomura Asset Management International Inc. Added+$40.8M
Capital World Investors Added+$38.3M
Davern Capital Partners, LP Added+$32.7M

Biggest sellers in Q2 2026

T. Rowe Price Investment Management, Inc. Trimmed-$174M
Bellevue Group AG Trimmed-$67.1M
Millennium Management LLC Trimmed-$60.5M
Citadel Advisors LLC Trimmed-$56.0M
Summit Partners Public Asset Management, LLC Trimmed-$48.9M
Ameriprise Financial Inc Trimmed-$47.0M
Squarepoint Ops LLC Trimmed-$46.5M
Geode Capital Management, LLC Trimmed-$32.9M
Zurich Insurance Group Ltd Sold out-$18.0M
J. Goldman & Co LP Trimmed-$15.5M

The change in shares since the quarter before, adjusted for stock splits and priced at the Q2 2026 value per share. Funds bought $1.5B and sold $927M; 196 added and 159 trimmed.

Questions about IONS ownership

Who owns IONS stock?: 513 institutional investment managers reported IONS positions in their Form 13F filings for Q2 2026, holding 179,752,611 shares worth $14.3B in total. FMR LLC reported the largest position.
Are funds buying or selling IONS?: In Q2 2026, 63 managers opened new IONS positions, 196 added, 159 trimmed and 46 sold out. Managers that filed in both quarters added a net 6,852,579 shares.
How current is this IONS institutional ownership data?: It covers holdings as of the end of Q2 2026. Managers have 45 days after the quarter ends to file Form 13F (by August 14, 2026 for Q2 2026), so positions may have changed since.

From the SEC's Form 13F data sets for Q2 2026: every 13F holdings report, matched to IONS by CUSIP. Options are left out. IONS news and filings · IONS insider trades · Top funds