Kara Wilson - 01 Apr 2026 Form 4 Insider Report for OneStream, Inc. (OS)

Reporting relationship: Director
Issuer ticker: OS
Reported as of: 01 Apr 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 02 Apr 2026, 18:46:38 UTC
Prior SEC filing: 17 Oct 2025
Source filing: View source filing
Reporting owner signature: /s/ Holly Koczot, attorney-in-fact

Key filing fact

Kara Wilson filed Form 4 for OneStream, Inc. (OS) on 02 Apr 2026.

Key facts

This page summarizes Kara Wilson's Form 4 filing for OneStream, Inc. (OS).
4 reported transactions and 3 derivative rows are listed below.
Accepted by SEC: 02 Apr 2026, 18:46.

Change

Previous filing in this sequence was filed on 17 Oct 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 0001529006 Primary reporting owner

WILSON KARA

Relationship: Director
Address: C/O ONESTREAM, INC., 191 N. CHESTER STREET, BIRMINGHAM
Signature: /s/ Holly Koczot, attorney-in-fact
Signature date: 02 Apr 2026

Reported non-derivative transactions

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

OS transaction

Class A Common Stock

Disposed to Issuer

Transaction value
Shares: -7,130
Change %: -100%
Price
Shares after: 0
Date: 01 Apr 2026
Ownership: Direct
Footnotes: F1, F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

OS transaction Derivative

Common Units

Disposed to Issuer

Transaction value
Shares: -293,411
Change %: -100%
Price
Shares after: 0
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Class D Common Stock
Underlying amount: 293,411
Exercise price
Footnotes: F1, F3

OS transaction Derivative

Stock Option (right to buy)

Disposed to Issuer

Transaction value
Shares: -50,000
Change %: -100%
Price
Shares after: 0
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Class A Common Stock
Underlying amount: 50,000
Exercise price: $16.40
Footnotes: F1, F4

OS transaction Derivative

Stock Option (right to buy)

Disposed to Issuer

Transaction value
Shares: -134,913
Change %: -100%
Price
Shares after: 0
Date: 01 Apr 2026
Ownership: Direct
Underlying class: Class A Common Stock
Underlying amount: 134,913
Exercise price: $20.00
Footnotes: F1, F4

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

Additional SEC filing notes

Filing notes and footnotes

Section 16 status

Kara Wilson is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may still apply in specific circumstances.

Explanation of responses 4 footnotes

Footnote F1

Pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 6, 2026, by and among OneStream, Inc. ("Issuer"), OneStream Software LLC, a subsidiary of Issuer ("Company LLC"), Onward AcquireCo Inc. ("Parent"), Onward Merger Sub 2, LLC ( "Merger Sub I") and Onward Merger Sub, Inc. ("Merger Sub II"), on April 1, 2026, Merger Sub 1 merged with and into Company LLC (the "First Merger"), with Company LLC surviving the First Merger and becoming a subsidiary of Parent, and Merger Sub II merged with and into Issuer (the "Second Merger" and together with the First Merger, the "Mergers"), with Issuer surviving the Second Merger and becoming a subsidiary of Parent.

Footnote F2

Represents an equal number of restricted stock units ("RSUs"). Pursuant to Issuer's outside director compensation policy, immediately before the effective time of the Mergers (the "Effective Time"), each RSU award held by a non-employee director that was outstanding and unvested as of immediately before the Effective Time (a "Director RSU Award") accelerated and became fully vested. At the Effective Time, each Director RSU Award was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) $24.00 (the "Per Share Price") multiplied by (b) the total number of shares of Issuer's Class A Common Stock covered by such Director RSU Award, less applicable withholding taxes.

Footnote F3

At the Effective Time, each Common Unit was cancelled and converted into the right to receive an amount in cash, without interest, equal to the Per Share Price, less applicable withholding taxes. Each corresponding share of Class C Common Stock was cancelled and converted into the right to receive $0.0001 in cash, without interest, less applicable withholding taxes.

Footnote F4

Pursuant to Issuer's outside director compensation policy, immediately prior to the Effective Time, the shares subject to the option became fully vested and immediately exercisable. At the Effective Time, the option was cancelled and converted into the right to receive an amount in cash, without interest, equal to the product of (a) the total number of shares of Class A Common Stock subject to the option multiplied by (b) the excess, if any, of the Per Share Price over the exercise price per share of such option, less applicable withholding taxes.