EXHIBIT 99.1

 

JOINT FILING AGREEMENT

 

The undersigned hereby agree that the statement on Schedule 13G with respect to the Shares of JAB ACQUISITION CORP I dated as of September 30, 2026 is, and any amendments thereto (including amendments on Schedule 13G) signed by each of the undersigned shall be, filed on behalf of each of us pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended.

 

Date: November 13, 2026 magnetar financial llc

 

  By: Magnetar Capital Partners LP, its Sole Member

 

  By: /s/ Hayley Stein
  Name: Hayley Stein
  Title: Attorney-in-fact for David J. Snyderman, Administrative Manager of Supernova Management LLC, GP of Magnetar Capital Partners LP, its Sole Member

 

Date: November 13, 2026 magnetar capital partners LP

 

  By: Supernova Management LLC, its General Partner

 

  By: /s/ Hayley Stein

 

  Name: Hayley Stein
  Title: Attorney-in-fact for David J. Snyderman, Administrative Manager of Supernova Management LLC, its General Partner

 

Date: November 13, 2026 supernova management llc

 

  By: /s/ Hayley Stein
  Name: Hayley Stein
  Title: Attorney-in-fact for David J. Snyderman, Administrative Manager of Supernova Management LLC

 

Date: November 13, 2026 DAVID J. SNYDERMAN

 

  By: /s/ Hayley Stein
  Name: Hayley Stein
  Title: Attorney-in-fact for David J. Snyderman