1 tracked superinvestor hold SIONNA THERAPEUTICS INC (SION), worth $141M combined, led by Andreas Halvorsen. Smart money is holding SION as of the latest 13F filings.
Current price
$7.18
-68.9%
1Y
Operating as a biopharmaceutical company, Sionna Therapeutics, Inc. is dedicated to transforming the treatment landscape for individuals with cystic fibrosis. This is achieved by developing innovative medicines designed to restore the normal function of the cystic fibrosis transmembrane conductance regulator.
Market cap
$1.8B
P/E
-20.82
Div yield
0.0%
Revenue YoY
0.0%
Analyst target
$27
Snapshot for context. For deep analysis use a stock screener — this page is about who owns it.
Superinvestors holding
1
tracked 13F / N-PORT funds
Combined value
$141M
disclosed long exposure
Tier-1 conviction
1
concentrated holders
Net this quarter
0
0 buying · 0 selling
Smart money is holding SION steady this quarter — buys and sells are balanced.
SIONNA THERAPEUTICS INC (SION) is held by 1 tracked funds worth $141M combined, 1 of them concentrated Tier-1 managers whose positions carry real conviction.
The largest position belongs to Andreas Halvorsen at 0.4% of their book — no single tracked manager treats it as an outsized, top-weighted bet.
Tracked holders were largely static this quarter — no new opens, adds or trims of size — suggesting the position is being held rather than actively traded.
| Investor | Move | % of their portfolio | Position value |
|---|---|---|---|
| Held | 0.4% | $141M |
Tier badge = signal quality: 1 concentrated conviction · 2 quant/multi (context) · 3 retail & diversified. Only Tier 1 holdings feed the consensus signal.
Which superinvestors own SION?
1 tracked funds hold SIONNA THERAPEUTICS INC (SION), the largest being Andreas Halvorsen (Viking Global Investors) at 0.4% of its 13F portfolio. 1 of them are concentrated Tier-1 conviction managers.
Is smart money buying or selling SION?
In the most recent 13F quarter, 0 tracked funds added or opened SION and 0 trimmed it.
How much SION do tracked funds hold?
Combined disclosed long exposure to SION across tracked superinvestors is $141M as of the Jun 2026 filings.
One email when a tracked manager opens, adds to or files to sell a position — from Form 4, 13D and Form 144, not the 45-day-old 13F.
Holdings aggregated from the latest SEC 13F & N-PORT filings via FMP · Jun 2026 quarter. Long equity positions only, reported with up to a 45-day delay — for activity between filings see real-time moves. Not financial advice.