144
0001885327
XXXXXXXX
LIVE
0002036042
Sionna Therapeutics, Inc.
001-42504
21 Hickory Drive
Suite 500
Waltham
MA
02451
6178192020
Atlas Venture Opportunity Fund II, L.P.
Shareholder
Common
Merrill Lynch
555 California Street
18th Floor
San Francisco
CA
94104
15418
496459.6
44139823
10/21/2025
NASDAQ
Common
03/04/2024
Private Placement
Issuer
N
15418
03/04/2024
Cash
N
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
09/29/2025
11468
345080.15
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
09/30/2025
2149
64594.43
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/01/2025
35
1048.25
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/03/2025
6548
196451.79
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/06/2025
2047
61430.47
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/10/2025
3511
105273.82
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/13/2025
10102
306888.66
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/14/2025
105
3144.75
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/15/2025
20098
615091.25
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/16/2025
29363
950063.36
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/17/2025
10604
343189.98
Atlas Venture Opportunity Fund II, L.P.
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/20/2025
9712
311691.10
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
09/29/2025
54637
1644065.58
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
09/30/2025
10239
307762.84
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/01/2025
165
4941.75
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/03/2025
31198
935996.16
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/06/2025
9753
292687.53
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/10/2025
16727
501542.37
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/13/2025
48130
1462141.27
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/14/2025
501
15004.95
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/15/2025
95758
2930635.29
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/16/2025
139897
4526479.35
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/17/2025
50520
1635039.38
Atlas Venture Fund XI, LP
400 Technology Sq.
10th Floor
Cambridge
MA
02139
Common
10/20/2025
46273
1485057.90
10/21/2025
02/25/2025
Ommer Chohan