Hudson Bay Capital Management LP

Position in IONS — Ionis Pharmaceuticals Inc

CIK 1393825 STAMFORD, CT

Back to IONS Full portfolio

Position in IONS

as of Mar 31, 2026 · filed May 13, 2026 Compact

Position Value

$22,159,059

-$15,418,191 QoQ

Shares Held

295,100

-37.9% QoQ

Ownership

0.179%

of shares outstanding

% of Portfolio

0.15%

of 13F equity value

Holder Rank

—

not a current holder

Holding Since

Mar 2020

25 quarters on record

Voting authority Sole 100.ToString("F0")% Shared 0.ToString("F0")% None 0.ToString("F0")%

Common Shares in IONS Over Time

Shares Held

Position Value (USD)

Derivatives in IONS

reported options exposure · as of Jun 30, 2022

CallValue

$1,480,800

CallShares

40,000

PutValue

PutShares

Notional value of option positions as reported on Form 13F. Calls and puts are disclosed separately and do not net against the common-share stake above.

Position in Biotechnology

Healthcare · as of Mar 31, 2026

Hudson Bay Capital Management LP holds $534,286,565 across 150 Biotechnology names. IONS ranks #5 (4.1% of the industry book) .

#	Ticker	Company	Shares	Value (USD)
1	BMRN	Biomarin Pharmaceutical Inc	974,776	$55,065,096
2	APLS	Apellis Pharmaceuticals, Inc.	1,190,416	$47,890,435
3	REGN	Regeneron Pharmaceuticals, Inc.	32,001	$24,725,252
4	BNTX	BioNTech SE	275,000	$24,442,000
5	IONS	Ionis Pharmaceuticals Inc This page	295,100	$22,159,059
6	ARGX	Argenx SE	30,000	$21,907,500
7	VRTX	Vertex Pharmaceuticals Inc / Ma	45,000	$20,094,300
8	IMCR	Immunocore Holdings plc	633,174	$19,090,196

All Filings in IONS

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27 filing rows on record

Report Date	Value (USD)	Shares	Change	Type	Discretion	Filed
2026-03-31	$22,159,059	295,100	-37.9%	Shares	Sole	2026-05-13
2025-12-31	$37,577,250	475,000	-7.8%	Shares	Sole	2026-02-13
2025-09-30	$33,691,300	515,000	-31.3%	Shares	Sole	2025-12-15
2025-06-30	$29,632,500	750,000	-28.6%	Shares	Sole	2025-08-18
2025-03-31	$31,675,483	1,049,900	+27.8%	Shares	Sole	2025-05-14
2024-12-31	$28,709,152	821,200	+7.1%	Shares	Sole	2025-02-14
2024-09-30	$30,722,014	766,900	+109.5%	Shares	Sole	2024-11-13
2024-06-30	$17,443,560	366,000	+9.1%	Shares	Sole	2024-08-14
2024-03-31	$14,543,925	335,500	+131.4%	Shares	Sole	2024-05-15
2023-12-31	$7,335,550	145,000	-23.7%	Shares	Sole	2024-02-14
2023-09-30	$8,618,400	190,000	-30.9%	Shares	Sole	2023-12-07
2023-06-30	$11,283,250	275,000	-10.1%	Shares	Sole	2023-08-14
2023-03-31	$10,929,292	305,800	+35.9%	Shares	Sole	2023-05-16
2022-12-31	$8,498,250	225,000	+12.6%	Shares	Sole	2023-02-14
2022-09-30	$8,837,154	199,800	+399.5%	Shares	Sole	2022-11-14
2022-06-30	$1,480,800	40,000	-78.4%	Call	Sole	2022-08-12
2022-06-30	$6,848,700	185,000	-11.9%	Shares	Sole	2022-08-12
2022-03-31	$7,778,400	210,000	+425.0%	Shares	Sole	2022-05-16
2022-03-31	$1,481,600	40,000	-86.9%	Call	Sole	2022-05-16
2021-12-31	$9,281,150	305,000	+15.1%	Shares	Sole	2022-02-14
2021-09-30	$8,888,100	265,000	+43.2%	Shares	Sole	2021-12-29
2021-06-30	$7,379,650	185,000	+41.9%	Shares	Sole	2021-08-16
2021-03-31	$5,862,784	130,400	-18.5%	Shares	Sole	2021-05-14
2020-12-31	$9,046,400	160,000	+28.0%	Shares	Sole	2021-03-04
2020-09-30	$5,931,250	125,000	-10.7%	Shares	Sole	2020-11-12
2020-06-30	$8,254,400	140,000	+211.1%	Shares	Sole	2020-08-12
2020-03-31	$2,127,600	45,000	—	Shares	Sole	2020-05-14
No filing history on record for this holder in this stock.