SION Sionna Therapeutics, Inc.

NASDAQ
$8.26

Sionna Therapeutics, Inc. (SION) Hedge Fund Activity

This view isolates hedge funds from the broader institutional ownership shown on the Institutional tab. A pension fund tracking an index may have no view on a stock; when a hedge fund builds or exits a position, that decision can carry information. This page measures those changes. Positions as of June 30, 2026.

Based on quarterly 13F long-equity filings. Changes compare reported quarter-end positions; filings can be reported up to 45 days later and do not represent a fund's complete exposure.

Hedge fund breadth
+21.74
14 buyers / 9 sellers
BUYING
Funds compared
28
funds with comparable SION positions
25 current holders · 21 prior-quarter holders
Net share change
+731.1K
+2.25M added, -1.52M cut
Position activity
7 new 7 increased 6 reduced 3 exited

Most significant moves

Ranked by conviction, not size — how much of the fund's own book the position represents, how far it moved, and what kind of fund made it.

Fund Action Shares changed Change Est. value Portfolio wt. Score
D. E. Shaw & Co., Inc. Quant New +101.6K $4.5M 0.0% 60
TWO SIGMA INVESTMENTS, LP Quant Sold Out -5.5K -100.0% $241.9K 0.0% 57
MARSHALL WACE, LLP Long/Short New +12.6K $554.2K 0.0% 56
ADAGE CAPITAL PARTNERS GP, L.L.C. Increased +1.45M +966.7% $63.8M 0.1% 56
Quadrature Capital Quant New +26.0K $1.1M 0.0% 55
Tudor Investment Corporation Macro New +22.6K $993.1K 0.0% 54
Hudson Bay Capital Management Event Sold Out -6.2K -100.0% $271.9K 0.0% 53
Trexquant Investment Quant New +23.8K $1.0M 0.0% 53
MILLENNIUM MANAGEMENT LLC Increased +136.1K +96.8% $6.0M 0.0% 52
OrbiMed Advisors Growth Healthcare Reduced -974.8K -27.6% $42.9M 2.1% 52

Most significant buyers

By move score, not size.

  • D. E. Shaw & Co., Inc. New · +101.6K
  • MARSHALL WACE, LLP New · +12.6K
  • ADAGE CAPITAL PARTNERS GP, L.L.C. Increased · +1.45M
  • Quadrature Capital New · +26.0K
  • Tudor Investment Corporation New · +22.6K

Most significant sellers

By move score, not size.

  • TWO SIGMA INVESTMENTS, LP Sold Out · -5.5K
  • Hudson Bay Capital Management Sold Out · -6.2K
  • OrbiMed Advisors Reduced · -974.8K
  • ExodusPoint Capital Management Sold Out · -7.2K
  • Point72 Asset Management, L.P. Reduced · -87.2K

Hedge fund positions

Fund Tier Shares Previous Change Change % Portfolio wt. Action Score
D. E. Shaw & Co., Inc. 1 101.6K 0 +101.6K 0.0% New 60
TWO SIGMA INVESTMENTS, LP 2 0 5.5K -5.5K -100.0% 0.0% Sold Out 57
MARSHALL WACE, LLP 2 12.6K 0 +12.6K 0.0% New 56
ADAGE CAPITAL PARTNERS GP, L.L.C. 2 1.6M 150.0K +1.45M +966.7% 0.1% Increased 56
Quadrature Capital 3 26.0K 0 +26.0K 0.0% New 55
Tudor Investment Corporation 2 22.6K 0 +22.6K 0.0% New 54
Hudson Bay Capital Management 3 0 6.2K -6.2K -100.0% 0.0% Sold Out 53
Trexquant Investment 3 23.8K 0 +23.8K 0.0% New 53
MILLENNIUM MANAGEMENT LLC 2 276.7K 140.6K +136.1K +96.8% 0.0% Increased 52
OrbiMed Advisors 2 2.6M 3.5M -974.8K -27.6% 2.1% Reduced 52
ExodusPoint Capital Management 3 0 7.2K -7.2K -100.0% 0.0% Sold Out 52
Jain Global 3 4.8K 0 +4.8K 0.0% New 52
Qube Research & Technologies Ltd 2 140.3K 42.2K +98.1K +232.2% 0.0% Increased 51
Engineers Gate 4 15.6K 0 +15.6K 0.0% New 48
Walleye Capital 3 97.3K 15.1K +82.3K +544.8% 0.0% Increased 47
Point72 Asset Management, L.P. 1 49.3K 136.5K -87.2K -63.9% 0.0% Reduced 46
Perceptive Advisors 1 905.0K 658.4K +246.6K +37.4% 0.6% Increased 46
Deerfield Management 1 680.9K 970.6K -289.7K -29.8% 0.4% Reduced 44
Integral Health Asset Management 2 75.0K 50.0K +25.0K +50.0% 0.1% Increased 40
Soleus Capital Management 2 177.7K 293.5K -115.8K -39.5% 0.3% Reduced 40
Squarepoint Ops LLC 2 5.4K 15.2K -9.8K -64.4% 0.0% Reduced 40
Quantbot Technologies 4 1.8K 178 +1.6K +922.5% 0.0% Increased 39
CITADEL ADVISORS LLC 1 1.1M 1.2M -19.3K -1.7% 0.0% Reduced 27
RA Capital Management 1 9.9M 9.9M 0 +0.0% 3.8% Unchanged 46
VIKING GLOBAL INVESTORS LP 1 3.2M 3.2M 0 +0.0% 0.4% Unchanged 27
Baker Bros. Advisors 1 400.0K 400.0K 0 +0.0% 0.1% Unchanged 25
Alyeska Investment Group, L.P. 2 136.2K 136.2K 0 +0.0% 0.0% Unchanged 20
Rock Springs Capital Management 3 99.4K 99.4K 0 +0.0% 0.2% Unchanged 18

Every fund above opens. Subscribers can see any manager's whole portfolio — every position, its weight, and what they bought, trimmed and exited last quarter.

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Hedge funds are identified from their 13F filings, which are due 45 days after quarter end and cover long U.S.-listed equity positions only. A fund's short book never appears, so a reduced position can mean a changed view or a changed hedge — the filing doesn't say which.