Alan D. Sobel - 15 Sep 2026 Form 4 Insider Report for Cytosorbents Corp (CTSO)

Reporting relationship: Director
Issuer ticker: CTSO
Reported as of: 15 Sep 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 16 Sep 2026, 16:05:14 UTC
Prior SEC filing: 08 Aug 2025
Source filing: View source filing
Reporting owner signature: /s/ Peter J. Mariani attorney-in-fact Alan D. Sobel

Key filing fact

Alan D. Sobel filed Form 4 for Cytosorbents Corp (CTSO) on 16 Sep 2026.

Key facts

This page summarizes Alan D. Sobel's Form 4 filing for Cytosorbents Corp (CTSO).
3 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 16 Sep 2026, 16:05.

Change

Previous filing in this sequence was filed on 08 Aug 2025.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001639386 Primary reporting owner

Sobel Alan D.

Relationship: Director
Address: C/O CYTOSORBENTS CORPORATION, 305 COLLEGE ROAD EAST, PRINCETON
Signature: /s/ Peter J. Mariani attorney-in-fact Alan D. Sobel
Signature date: 16 Sep 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

CTSO transaction

Common Stock

Purchase

Transaction value
Shares: +1,900
Change %: +26%
Price: $6.12^*
Shares after: 9,287
Date: 15 Sep 2026
Ownership: Direct
Footnotes: F1, F2, F3

CTSO transaction

Common Stock

Purchase

Transaction value
Shares: +500
Change %: +5.4%
Price: $6.05^*
Shares after: 9,787
Date: 15 Sep 2026
Ownership: Direct
Footnotes: F1, F2, F3

CTSO transaction

Common Stock

Purchase

Transaction value
Shares: +100
Change %: +1%
Price: $6.01^*
Shares after: 9,887
Date: 15 Sep 2026
Ownership: Direct
Footnotes: F1, F2, F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

These transactions reported on this Form 4 reflect open market purchases made by the Reporting Person.

Footnote F2

Includes (i) the following restricted stock units ("RSUs") that will be settled into Common Stock upon vesting upon a "Change in Control" of CytoSorbents Corporation (the "Issuer"), as defined in the CytoSorbents Corporation 2014 Long-Term Incentive Plan (the "Plan"): (a) 165 RSUs granted on March 15, 2018, (b) 300 RSUs granted on February 24, 2017, (c) 250 RSUs granted on June 7, 2016, and (d) 2,750 RSUs granted on April 8, 2015 and (ii) 6,422 shares of Common Stock owned directly by the Reporting Person.

Footnote F3

Reflects the 1-for-20 reverse stock split effected by the Issuer on September 8, 2026.