Magnetar Financial LLC and affiliated reporting persons filed an amended Schedule 13G with the SEC on November 13, 2026, disclosing beneficial ownership of 1,200,000 ordinary shares of AmperCap Acquisition Co as of September 30, 2026.

Key Highlights

  • Aggregate beneficial ownership: Each of the four reporting persons may be deemed to beneficially own 1,200,000 ordinary shares of AmperCap Acquisition Co, par value $0.0001 per share.
  • Percent of class: The 1,200,000 shares represent approximately 6.01% of total shares outstanding, based on approximately 19,958,575 shares outstanding as reported by the issuer.
  • Shared voting and dispositive power: All 1,200,000 shares carry shared voting power and shared dispositive power; sole voting and sole dispositive power are each reported as 0.
  • Reporting persons: The four reporting persons are Magnetar Financial LLC, Magnetar Capital Partners LP, Supernova Management LLC, and David J. Snyderman.
  • Shares distributed across multiple funds: The 1,200,000 shares are held across seven Magnetar Funds, with the largest single allocation being 288,000 shares held for Magnetar Constellation Master Fund, Ltd.
  • Event date: The date of the event requiring this filing is September 30, 2026.

Magnetar Financial's Ownership Structure in AmperCap Acquisition

According to the amended Schedule 13G filing, Magnetar Financial LLC serves as the investment adviser to the Magnetar Funds and, as such, exercises voting and investment power over the shares held in those funds' accounts. Magnetar Capital Partners LP is reported as the sole member and parent holding company of Magnetar Financial. Supernova Management LLC is identified as the general partner of Magnetar Capital Partners, and David J. Snyderman is listed as the administrative manager of Supernova Management. All four entities are based at 1603 Orrington Avenue, 13th Floor, Evanston, Illinois 60201, according to the filing.

The filing discloses that the 1,200,000 shares are distributed across seven funds as follows: 288,000 shares for Magnetar Constellation Master Fund, Ltd; 252,000 shares for Magnetar Structured Credit Fund, LP; 204,000 shares each for Magnetar Alpha Star Fund LLC, Magnetar Lake Credit Fund LLC, and Magnetar Xing He Master Fund Ltd; 36,000 shares for Magnetar Waterfront Series A LLC; and 12,000 shares for Magnetar Capital Master Fund Ltd. The 6.01% ownership percentage was calculated using the approximately 19,958,575 shares outstanding as reported by the issuer in a Form 10-Q filed on August 13, 2026, the filing states.

The filing is designated Amendment No. 1 to a previously filed Schedule 13G. The reporting persons certified, according to the filing, that the securities "were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer." The shares are ordinary shares with CUSIP number G0344N107. The filing was signed by Hayley Stein as attorney-in-fact for David J. Snyderman on November 13, 2026.

What Was Disclosed

Magnetar Financial LLC and three affiliated persons filed an amended Schedule 13G disclosing combined beneficial ownership of 1,200,000 ordinary shares, or approximately 6.01%, of AmperCap Acquisition Co as of September 30, 2026, with all voting and dispositive power held on a shared basis.