Mizuho Bank now holds 23,559,673 common shares of Rakuten Bank, or 5.81% of 405,405,896 issued shares, according to a large-shareholding report filed on 8 October 2026 with the Kanto Local Finance Bureau. The obligation to report arose on 1 October. The report lists no earlier holding ratio.
How the shares arrived
The stake came through the transaction already covered in our earlier report on Rakuten Bank's takeover of Rakuten Card. On 1 October, Rakuten Bank was the parent in a share delivery in which Rakuten Card was the subsidiary and Mizuho Bank was the transferor. Mizuho received 23,559,673 Class A preferred shares of Rakuten Bank. The same day it exercised its acquisition right on those shares and took the same number of common shares. The report records the Class A shares as disposed of on conversion.
The report shows acquisition funds of zero: no own funds, no borrowings, and nothing under "other" except the description of the share delivery and conversion. That figure does not mean nothing changed hands. The filing does not give an issue price for the preferred shares or the terms of the delivery.
Governance rights and limits
Mizuho lists its holding purpose as part of its group strategy and as "important proposal acts". Under a capital and business alliance agreement dated 20 May 2026, it may name one outside director of Rakuten Card, a subsidiary of Rakuten Bank, for as long as it holds a certain number of Rakuten Bank shares or more. The filing does not state that threshold. Mizuho may notify Rakuten Bank of a nomination or a removal, and says it plans to nominate a candidate. The right covers a seat at Rakuten Card, not at Rakuten Bank.
The same agreement restricts Mizuho. It cannot transfer any of its Rakuten Bank shares without Rakuten Bank's prior written consent. If it wants to sell, it must notify Rakuten Bank and negotiate first with a party Rakuten Bank designates. It has also promised not to acquire more Rakuten Bank shares, directly or indirectly, or to discuss doing so with third parties, without Rakuten Bank's prior consent.
A second filer, a different holding
The report is a joint filing by two parties. Asset Management One holds 2,794,200 common shares, or 0.69%, under investment trusts or discretionary mandates. It lists ¥1.35bn of client assets as the source of funds, and notes that client assets are revalued to market value when the accounts are closed, so the book value may differ from the original cost. Its holding is separate from Mizuho's alliance rights: the filing gives it no director nomination right.
The filing totals the two holdings at 26,353,873 shares, or 6.50%. Mizuho Bank's own 5.81% is the figure tied to the alliance terms.