Mizuho Financial Group, Inc. filed Amendment No. 4 to its Schedule 13G on November 12, 2026, disclosing beneficial ownership of 549 common shares of Black Hawk Acquisition Corp as of September 30, 2026.

Key Highlights

  • Beneficial ownership: Mizuho Financial Group, Inc. reported aggregate beneficial ownership of 549 common shares of Black Hawk Acquisition Corp.
  • Percent of class: The 549 shares represent 0.0% of the class, as stated in the filing.
  • Sole voting and dispositive power: All 549 shares carry sole voting power and sole dispositive power; shared voting and shared dispositive power are each reported as 0.
  • Triggering event date: The date of the event requiring this filing is stated as September 30, 2026.
  • Indirect beneficial ownership: According to the filing, Mizuho Financial Group, Inc., Mizuho Bank, Ltd., and Mizuho Americas LLC "may be deemed to be indirect beneficial owners of said equity securities directly held by Mizuho Securities USA LLC which is their wholly-owned subsidiary."
  • Filing classification: Mizuho Financial Group, Inc. is identified as a Parent Holding Company in the filing.

Mizuho Financial Group's Amendment No. 4 Filing on Black Hawk Acquisition Corp Shares

Mizuho Financial Group, Inc., a Japan-incorporated financial institution headquartered at 1-5-5, Otemachi, Chiyoda-ku, Tokyo, 100-8176, Japan, filed Amendment No. 4 to Schedule 13G with the SEC on November 12, 2026. The filing covers common shares of Black Hawk Acquisition Corp (CUSIP G1148A101), whose principal executive offices are located at 4125 Blackhawk Plaza Circle, Suite 166, Danville, CA 94506, according to the filing.

The filing discloses that Mizuho Financial Group beneficially owns 549 common shares, representing 0.0% of the outstanding class. The reporting person holds sole voting power and sole dispositive power over all 549 shares, with no shared voting or dispositive power reported. The filing notes that the securities are held indirectly, as Mizuho Securities USA LLC, a wholly-owned subsidiary, directly holds the shares, and Mizuho Financial Group, Inc., Mizuho Bank, Ltd., and Mizuho Americas LLC may be deemed indirect beneficial owners as a result.

The filing was signed by Takahiro Katsura, Managing Director, Global Corporate Function Coordination Department of Mizuho Financial Group, Inc., and dated November 12, 2026. The certification states that the referenced 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 of the securities," as quoted in the filing. Item 5 of the filing designates the holding as ownership of 5 percent or less of a class. The filing does not name a stock exchange or trading symbol for Black Hawk Acquisition Corp's common shares.

What Was Disclosed

Mizuho Financial Group, Inc. disclosed through Amendment No. 4 to Schedule 13G that it indirectly beneficially owns 549 common shares of Black Hawk Acquisition Corp, amounting to 0.0% of the class, with the triggering event dated September 30, 2026.