OS Therapies OSTX Insider Ownership

NYSE OSTX
$1.62 -0.03 (-2.12%)
As of: Sep 29, 2026 · 3:59 PM EDT

Insider Holdings by Owner

6.29Mn Shares

Insider Ownership Statistics

as of 30 Sep, 2026
Insider Ownership
131.68%
■0% pp QoQ
Shares Held by Insiders
6.29Mn
filed for Sep 2026
■0.00% QoQ
Shares Outstanding
4.77Mn
4,774,637 shares
Direct Holdings
2.47Mn
Indirect: 3.81Mn
Net Shares Traded (QoQ)
0
no net change in Sep 2026
Insiders Holding Shares
4
with Form 4 holdings on file

Shares Owned by Insiders

Shares held % of outstanding
Latest —
Average ownership —
Peak ownership —

Shares Purchased/Sold by Insiders

Bought Sold
Latest quarter —
Net over range —
Buying quarters —

Insider Ownership Summary

Quarter ending 30 Sep, 2026

As of September 29, 2026, the three largest insider holders of OSTX are Shalom Auerbach (TenPercentOwner, 2.66Mn shares), Paul A. Romness (President And Ceo, 2.47Mn shares), John Ciccio (Director, 435.83K shares).

Form 4 Holdings

Insiders Holding OSTX

Insiders 4
Shares held 6.29Mn
Of outstanding 131.68%
# Insider Position Direct Indirect Total Share of Insiders Last Filed
1 Shalom Auerbach TenPercentOwner 0 2,664,199 2,664,199 42.4% 09 May, 2025
2 Paul A. Romness President And Ceo 2,473,000 0 2,473,000 39.3% 28 Feb, 2025
3 John Ciccio Director 0 575,100 575,100 9.1% 06 Aug, 2024
4 Theodore F. Search Director 0 575,100 575,100 9.1% 06 Aug, 2024

Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.

Form 4 Filings

29 Insider Transactions

Source SEC Form 4
Latest quarter Sep 2026
Download Data
Date Insider Position Transaction Shares Price Value Shares Held After Ownership
22 Jan, 2026 Olivier Roger Jarry Director Acquired A 50,000 $0.00 $0 50,000 Direct
22 Jan, 2026 Karim Galzahr Director Acquired A 50,000 $0.00 $0 50,000 Direct
22 Jan, 2026 Robert Petit Officer Acquired A 100,000 $0.00 $0 100,000 Direct
22 Jan, 2026 Paul A. Romness President And Ceo Acquired A 1,000,000 $0.00 $0 1,000,000 Direct
22 Jan, 2026 Christopher P. Acevedo Chief Financial Officer Acquired A 100,000 $0.00 $0 100,000 Direct
22 Jan, 2026 Avril Suzette Mckean-Dieser Director Acquired A 50,000 $0.00 $0 50,000 Direct
22 Jan, 2026 Theodore F. Search Director Acquired A 50,000 $0.00 $0 50,000 Direct
22 Jan, 2026 John Ciccio Director Acquired A 50,000 $0.00 $0 50,000 Direct
21 Oct, 2025 Karim Galzahr Director Acquired A 140,000 $0.00 $0 140,000 Direct
21 Oct, 2025 Olivier Roger Jarry Director Acquired A 140,000 $0.00 $0 140,000 Direct
21 Oct, 2025 Avril Suzette Mckean-Dieser Director Acquired A 140,000 $0.00 $0 140,000 Direct
21 Oct, 2025 Robert Petit Officer Acquired A 500,000 $0.00 $0 500,000 Direct
21 Oct, 2025 Paul A. Romness President And Ceo Acquired A 1,950,000 $0.00 $0 1,950,000 Direct
21 Oct, 2025 Christopher P. Acevedo Chief Financial Officer Acquired A 200,000 $0.00 $0 200,000 Direct
21 Oct, 2025 John Ciccio Director Acquired A 140,000 $0.00 $0 140,000 Direct
21 Oct, 2025 Theodore F. Search Director Acquired A 140,000 $0.00 $0 140,000 Direct
07 May, 2025 Shalom Auerbach TenPercentOwner Disposed S 82,000 $2.00 $163.92K 2,664,199 Indirect
09 Apr, 2025 Shalom Auerbach TenPercentOwner Disposed S 50,012 $1.35 $67.67K 2,756,199 Indirect
10 Apr, 2025 Shalom Auerbach TenPercentOwner Disposed S 10,000 $1.39 $13.90K 2,746,199 Indirect
27 Feb, 2025 Shalom Auerbach TenPercentOwner Disposed J 225,000 $1.64 $369.00K 2,806,211 Indirect