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Sionna Therapeutics, Inc. (SION) institutional ownership

Latest close $45.70 Jul 24, 2026
Market cap$747M 52-week range SectorHealthcare
Funds holding · Q1 2026
107
reported SION position changes
Top owners · Q1 2026
No disclosed owners are available.
Institutional activity · Q1 2026
Activity unavailable N/A
69 buyers · 38 sellers

Sionna Therapeutics, Inc. (SION) price and institutional activity

Dates

Q1 2026

$0 bought by 69 investors
Jennison Associates LLCSio Capital Management, LLC +67 more
$0 sold by 38 investors
Perceptive Advisors LLCAberdeen Group PLC +36 more
Bought Sold Totals per quarter; hover a bar for the names.

Sionna Therapeutics, Inc. (SION) institutional activity · 38

Investor Type Est. change Change Δ Own Date
Perceptive Advisors LLC · Reduced
Change −521K Date Q1 2026
Perceptive Advisors LLC Reduced· Q1 2026 −521K Q1 2026
Aberdeen Group PLC · Reduced
Change −276K Date Q1 2026
Aberdeen Group PLC Reduced· Q1 2026 −276K Q1 2026
Tpg Gp A, LLC · Reduced
Change −250K Date Q1 2026
Tpg Gp A, LLC Reduced· Q1 2026 −250K Q1 2026
Invesco Ltd. · Reduced
Change −100K Δ Own −90.3% Date Q1 2026
Invesco Ltd. Reduced· Q1 2026 −100K −90.3% Q1 2026
T. Rowe Price Associates · Reduced
Change −75K Date Q1 2026
T. Rowe Price Associates Reduced· Q1 2026 −75K Q1 2026
Longaeva Partners L.P. · Reduced
Change −67K Date Q1 2026
Longaeva Partners L.P. Reduced· Q1 2026 −67K Q1 2026
Superstring Capital Management LP · Reduced
Change −40K Date Q1 2026
Superstring Capital Management LP Reduced· Q1 2026 −40K Q1 2026
Orbimed Advisors LLC · Reduced
Change −31K Date Q1 2026
Orbimed Advisors LLC Reduced· Q1 2026 −31K Q1 2026
Td Asset Management Inc · Reduced
Change −30K Date Q1 2026
Td Asset Management Inc Reduced· Q1 2026 −30K Q1 2026
Barclays PLC · Reduced
Change −30K Date Q1 2026
Barclays PLC Reduced· Q1 2026 −30K Q1 2026
Ameriprise Financial Inc · Reduced
Change −20K Date Q1 2026
Ameriprise Financial Inc Reduced· Q1 2026 −20K Q1 2026
Wells Fargo & Company · Reduced
Change −12K Date Q1 2026
Wells Fargo & Company Reduced· Q1 2026 −12K Q1 2026
SG Americas Securities, LLC · Exited
Change −11K Δ Own −100.0% Date Q1 2026
SG Americas Securities, LLC Exited· Q1 2026 −11K −100.0% Q1 2026
Driehaus Capital Management LLC · Reduced
Change −7K Date Q1 2026
Driehaus Capital Management LLC Reduced· Q1 2026 −7K Q1 2026
American Century Companies Inc · Exited
Change −6K Δ Own −100.0% Date Q1 2026
American Century Companies Inc Exited· Q1 2026 −6K −100.0% Q1 2026
Data through Q1 2026 · filed May 29, 2026
15 of 38

Famous investor activity in Sionna Therapeutics, Inc. (SION)

Sionna Therapeutics, Inc. (SION) insider trading

Company insiders, action and economics first; trade and filed dates last.
Dates
Insider Title Type Price Qty Value Owned ΔOwn Trade date Filed date
Thompson Peter A. · Director Sell −$3.9M
Price $44.86 Qty −86K Owned 2.5M ΔOwn −3.4% Trade date Jul 7, 2026 Filed date Jul 9, 2026
Thompson Peter A. Director Sell $44.86 −86K −$3.9M 2.5M −3.4% Jul 7, 2026 Jul 9, 2026
Orbimed Advisors LLC · Director Sell −$3.9M
Price $44.86 Qty −86K Owned 2.5M ΔOwn −3.4% Trade date Jul 7, 2026 Filed date Jul 9, 2026
Orbimed Advisors LLC Director Sell $44.86 −86K −$3.9M 2.5M −3.4% Jul 7, 2026 Jul 9, 2026
Fitzpatrick Jennifer · Officer Sell −$447K
Price $43.60 Qty −10K Owned 0 ΔOwn −100.0% Trade date Jul 6, 2026 Filed date Jul 7, 2026
Fitzpatrick Jennifer Officer Sell $43.60 −10K −$447K 0 −100.0% Jul 6, 2026 Jul 7, 2026
Fitzpatrick Jennifer · Officer 2 operations 0
Price $6.11 Owned 41K Trade date Jul 6, 2026 Filed date Jul 7, 2026
Fitzpatrick Jennifer Officer 2 operations $6.11 0 41K Jul 6, 2026 Jul 7, 2026
Thompson Peter A. · Director Sell −$5.3M
Price $45.50 Qty −116K Owned 2.6M ΔOwn −4.3% Trade date Jun 30, 2026 Filed date Jul 2, 2026
Thompson Peter A. Director Sell $45.50 −116K −$5.3M 2.6M −4.3% Jun 30, 2026 Jul 2, 2026
Orbimed Advisors LLC · Director Sell −$5.3M
Price $45.50 Qty −116K Owned 2.6M ΔOwn −4.3% Trade date Jun 30, 2026 Filed date Jul 2, 2026
Orbimed Advisors LLC Director Sell $45.50 −116K −$5.3M 2.6M −4.3% Jun 30, 2026 Jul 2, 2026
Stelzer Laurie · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Stelzer Laurie Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Viney Joanne L. · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Viney Joanne L. Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Thompson Peter A. · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Thompson Peter A. Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Ra Capital Management, L.P. · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Ra Capital Management, L.P. Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Ruddy Marcella K. · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Ruddy Marcella K. Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Resnick Joshua · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Resnick Joshua Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Fleming Harold Edward · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Fleming Harold Edward Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Clancy Paul J. · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Clancy Paul J. Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
Booth Bruce · Director Grant (A) 17K
Owned 17K Trade date Jun 17, 2026 Filed date Jun 18, 2026
Booth Bruce Director Grant (A) 17K 17K Jun 17, 2026 Jun 18, 2026
15 of 103
15 of 103 Sign in to continue to older insider transactions.

Sionna Therapeutics, Inc. (SION) activist and large shareholders

Dates
Owner/Filer identity Shares reported % of shares outstanding Filing date
Viking Global Investors LP 3.2M
% of shares outstanding 7.1% Filing date May 15, 2026
Viking Global Investors LP 3.2M 7.1% May 15, 2026
Qatar Investment Authority 2.0M
% of shares outstanding 4.5% Filing date May 12, 2026
Qatar Investment Authority 2.0M 4.5% May 12, 2026
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Sionna Therapeutics, Inc. (SION) ownership FAQ

Who owns SION?

107 reporting institutions disclosed SION position changes in the Q1 2026 snapshot.

How is institutional activity calculated?

For each manager, WhoBought compares accepted consecutive 13F share counts. Share change is current shares minus prior shares. Estimated dollar change is that signed share change multiplied by the split-adjusted quarter-mean close. The activity table on this page uses Q1 2026.

What are activist and large shareholder filings?

An investor crossing 5% of a share class generally files Schedule 13D for activist intent or Schedule 13G for a passive position. The technical form names appear here rather than in the activity rows.

Where does this data come from?

Ownership and institutional activity come from SEC Form 13F filings. Insider activity comes from SEC Form 4, and large-shareholder activity from SEC Schedules 13D and 13G. FMP supplies price data only. Company logos use the local verified Parqet cache with one shared fallback.

Why are ownership reports delayed?

Form 13F is a quarterly disclosure and is normally filed after the quarter ends. Every ownership and activity value therefore names its represented period; it is not presented as a live position.

How are missing table values shown?

A muted dash marks a missing table value. It means the filing omitted the value, comparable data is unavailable, or no prior position exists for comparison.