Sionna Therapeutics (SION) CFO Ridloff sold 23,416 shares for $602K at an average $25.70 under a 10b5-1 plan
Insider transactions reported
Elena Ridloff (CFO & Head of Corp. Dev. at Sionna Therapeutics Inc., SION) reported that they sold 23,416 shares for $602K at an average $25.70 between Aug 26, 2025 and Aug 28, 2025. After these transactions the filing shows 48,116 shares held directly.
- Reporting person
- Ridloff Elena
- Role
- CFO & Head of Corp. Dev.
| Date | Type | Security | Shares | Price | Value | Held after |
|---|---|---|---|---|---|---|
| Aug 26, 2025 | Open-market sale (S) | Common Stock1, 2 | -3,700 | $25.13 | $93K | 67,832 direct |
| Aug 27, 2025 | Open-market sale (S) | Common Stock1, 3 | -3,618 | $25.10 | $90.8K | 64,214 direct |
| Aug 28, 2025 | Open-market sale (S) | Common Stock1, 4 | -16,098 | $25.97 | $418K | 48,116 direct |
Holdings before and after
- Common Stock: 71,532 to 48,116 direct
Footnotes from the filing
- 1. This transaction was automatically executed pursuant to a Rule 10b5-1 trading plan adopted on May 20, 2025.
- 2. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $25.00 to $25.28, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price at which the transactions were effected.
Transaction codes in this filing
- Open-market sale:
- Code S marks a sale in the open market or a private deal. The insider received cash for these securities.
FAQ
What did Ridloff report in this SION Form 4?
Elena Ridloff (CFO & Head of Corp. Dev. at Sionna Therapeutics Inc., SION) reported that they sold 23,416 shares for $602K at an average $25.70 between Aug 26, 2025 and Aug 28, 2025. After these transactions the filing shows 48,116 shares held directly.
How many SION shares does Ridloff hold after this filing?
The filing shows 48,116 shares held directly after the reported transactions. Form 4 reports only the positions it lists, so this may not be every holding.
Was this SION insider sale made under a 10b5-1 plan?
The filing's footnotes mention a Rule 10b5-1 trading plan. Such a plan sets the terms of future trades in advance.
What does transaction code S mean on an SEC Form 4?
Code S marks a sale in the open market or a private deal. The insider received cash for these securities.
Historical context for SION
Earlier insider filings at SION
- Aug 21, 2025President & CEO Cloonan Michael exercised 25,000 shares at a strike of $6.11 and sold $568,750 worth of shares (25,000 units at $22.75) (SEC Form 4)
- Aug 21, 2025CFO & Head of Corp. Dev. Ridloff Elena sold $1,124,335 worth of shares (52,000 units at $21.62), decreasing direct ownership by 42% to 71,532 units (SEC Form 4)
- Jul 1, 2025Large owner Tpg Gp A, Llc bought $950,400 worth of shares (60,000 units at $15.84) (SEC Form 4)
- Jun 16, 2025SEC Form 4 filed by Director Ra Capital Management, L.P.
- Jun 16, 2025SEC Form 4 filed by Director Viney Joanne L.
- Market cap
- 30-day
- Sector
- Health Care
- Industry
- Biotechnology: Pharmaceutical Preparations
- Listed since
- 2025
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