Sionna Therapeutics, Inc.

Sionna Therapeutics, Inc. insiders are currently net sellers of SION stock, showing bearish sentiment over the past 90 days. Total sales of $78.5M outpace purchases of $950.4K, creating a net outflow of $77.6M.

Sionna Therapeutics, Inc. has 12 active insiders who have filed SEC Form 4 transactions in the past 90 days. Bruce Booth (Executive) leads with 50 transactions totaling $22.1M. Capital Nexus Fund Iii, L.p. Ra (Executive) follows with 8 transactions worth $14.8M. Open-market purchases require insiders to invest their own capital, demonstrating genuine conviction.

The Insider Alignment Score measures the ratio of buying to selling activity on a 0-100 scale. Sionna Therapeutics, Inc.'s current score of 1/100 indicates bearish insider sentiment. Scores below 40 indicate selling pressure exceeds buying. Insider selling often reflects diversification needs, tax optimization, or estate planning.

The most recent insider transaction occurred on Mar 5, 2026, when Fitzpatrick Jennifer (Chief Legal Officer) disposed of 10,250 shares at $0.00 per share for $0. This appears to be a discretionary trade.

Based on SEC Form 4 filings from the past 90 days, SION insider trading sentiment is currently bearish with an Alignment Score of 1/100. The negative net flow of $77.6M shows more selling than buying. However, 0% of recent transactions are 10b5-1 scheduled trades.

SEC Form 4 is the primary disclosure mechanism for insider trading at publicly traded companies like Sionna Therapeutics, Inc.. Corporate insiders must file within two business days of any transaction, making it one of the most timely sources of executive sentiment. At SION, we track all Form 4 filings—currently showing 158 transactions from 12 insiders over 90 days.

A 10b5-1 plan allows Sionna Therapeutics, Inc. executives to pre-schedule stock sales when they don't possess material non-public information. At SION, approximately 0% of recent transactions are 10b5-1 trades. Most trading activity at SION appears discretionary, making insider signals more meaningful.

You can monitor Sionna Therapeutics, Inc. (SION) insider trading activity on this page, which updates within hours of new SEC Form 4 filings. We track all 12 active insiders and provide real-time transaction feeds, the Alignment Score, 10b5-1 vs. discretionary breakdowns, and direct links to SEC EDGAR filings.

Our Alignment Score measures the ratio of insider buying to selling on a scale of 0-100. A score above 70 indicates strong bullish sentiment, while below 30 suggests bearish activity. Sionna Therapeutics, Inc.'s current score of 1/100 indicates bearish sentiment with significant insider selling pressure. This is calculated from $950.4K in purchases versus $78.5M in sales over 90 days, resulting in a net flow of -$77.6M.

SEC Form 4 filings are mandatory reports that Sionna Therapeutics, Inc. insiders must submit within 2 business days. Each filing includes the insider's name, relationship, transaction type, shares, and price. Transaction codes: P (purchase), S (sale), A (award), M (option exercise), G (gift). At SION, the most common type is "S" with 47 occurrences. The most recent Form 4 was filed on Mar 5, 2026 by Fitzpatrick Jennifer.

Rule 10b5-1 allows corporate insiders to establish pre-scheduled trading plans when they don't possess material non-public information. At Sionna Therapeutics, Inc., approximately 0% of recent transactions are executed under 10b5-1 plans, while 100% appear to be discretionary trades. The low percentage means most insider activity at SION represents discretionary decisions with more informational value.