SION

Sionna Therapeutics, Inc. Common Stock
SION

Overview Fund Activity

64 hedge funds and large institutions have $754M invested in Sionna Therapeutics, Inc. Common Stock in 2025 Q2 according to their latest regulatory filings, with 25 funds opening new positions, 18 increasing their positions, 10 reducing their positions, and 8 closing their positions.

Holders
64
Holders Change
+17
Holders Change %
+36.17%
% of All Funds
0.86%
Holding in Top 10
4
Holding in Top 10 Change
+2
Holding in Top 10 Change %
+100%
% of All Funds
0.05%
New
25
Increased
18
Reduced
10
Closed
8
Calls
–
Puts
–
Net Calls
–
Net Calls Change
–

Top Buyers

1
B
1
Braidwell
Connecticut
$18.8M
2
BlackRock
2
BlackRock
New York
$11.1M
3
Viking Global Investors
3
Viking Global Investors
Connecticut
$55.4M
4
DM
4
Deerfield Management
New York
$16.8M
5
Aberdeen Group
5
Aberdeen Group
United Kingdom
$16.5M

Top Sellers

1
DCM
1
Driehaus Capital Management
Illinois
$1.45M
2
Citadel Advisors
2
Citadel Advisors
Florida
$2.25M
3
Millennium Management
3
Millennium Management
New York
$243K
4
ZP
4
Zimmer Partners
New York
$0
5
T. Rowe Price Associates
5
T. Rowe Price Associates
Maryland
$14.9M
Name Market Value Shares Shares
Change 		Shares
Change %
RCM
1
RA Capital Management
Massachusetts
$181M 10,445,322 – –
TGA
2
TPG GP A
Texas
$117M 6,744,962 +60,000 +0.9%
O
3
OrbiMed
New York
$64.3M 3,704,959 – –
AVLSA
4
Atlas Venture Life Science Advisors
Massachusetts
$64.1M 3,694,020 – –
Viking Global Investors
5
Viking Global Investors
Connecticut
$55.4M 3,195,181 +242,427 +8%
ES
6
Enavate Sciences
California
$43M 2,478,030 – –
JPMorgan Chase & Co
7
JPMorgan Chase & Co
New York
$38.5M 2,221,188 +51,589 +2%
PA
8
Perceptive Advisors
New York
$21.1M 1,216,045 -35,056 -3%
B
9
Braidwell
Connecticut
$18.8M 1,081,855 +1,081,855 New
DM
10
Deerfield Management
New York
$16.8M 970,590 +223,590 +30%
Aberdeen Group
11
Aberdeen Group
United Kingdom
$16.5M 950,547 +204,583 +27%
T. Rowe Price Associates
12
T. Rowe Price Associates
Maryland
$14.9M 861,238 -134,974 -14%
Jennison Associates
13
Jennison Associates
New York
$13.1M 752,800 -107,127 -12%
BlackRock
14
BlackRock
New York
$11.1M 637,104 +438,708 +221%
Vanguard Group
15
Vanguard Group
Pennsylvania
$10.9M 630,351 +84,184 +15%
Franklin Resources
16
Franklin Resources
California
$8.68M 500,023 – –
BBA
17
Baker Bros. Advisors
New York
$6.94M 400,000 – –
SCM
18
Soleus Capital Management
Connecticut
$6.52M 376,000 +136,000 +57%
SL
19
Siren LLC
Connecticut
$5.64M 325,000 – –
Geode Capital Management
20
Geode Capital Management
Massachusetts
$5.02M 289,275 +153,712 +113%
Ameriprise
21
Ameriprise
Minnesota
$4.11M 236,813 +27,547 +13%
Alyeska Investment Group
22
Alyeska Investment Group
Illinois
$3.23M 186,222 – –
SCM
23
Silverarc Capital Management
Massachusetts
$3.23M 186,015 +71,877 +63%
Prudential Financial
24
Prudential Financial
New Jersey
$2.35M 135,185 +72,185 +115%
Citadel Advisors
25
Citadel Advisors
Florida
$2.25M 129,912 -196,588 -60%
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