1 tracked superinvestor hold SIONNA THERAPEUTICS INC (SION), worth $128M combined, led by Andreas Halvorsen. Smart money is holding SION as of the latest 13F filings.
Current price
$44.94
Sionna Therapeutics, Inc. is a biopharmaceutical company. The Company provides treatment paradigm for cystic fibrosis patients by developing medicines that normalize the 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
$54
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
$128M
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 $128M 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% | $128M |
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 $128M as of the Mar 2026 filings.
Holdings aggregated from the latest SEC 13F & N-PORT filings via FMP · Mar 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.