Resolution criteria

• Resolves to the single person who first becomes Prime Minister of Japan after Shigeru Ishiba announced his resignation on September 7, 2025. “Becomes PM” means: (1) designated by the National Diet under Article 67, and (2) appointed by the Emperor and listed as Prime Minister on the PM’s Office (Kantei) “List of Ministers” page for the new cabinet. Acting/caretaker roles or party leadership alone do not count. If the Diet reappoints Ishiba, “Shigeru Ishiba” would resolve Yes. (shugiin.go.jp, japan.kantei.go.jp)

Background

• Ishiba resigned following successive election losses; he will serve as caretaker until a successor is chosen, with the LDP expected to hold a rapid leadership contest. (reuters.com, politico.com)

• How the PM is chosen: the Diet elects the PM; if the two houses disagree, the House of Representatives prevails. Verification will use the Kantei cabinet page for the incoming PM. (shugiin.go.jp, japan.kantei.go.jp)

• About listed answers:

  • Sanae Takaichi — conservative LDP figure and former minister; would be Japan’s first female PM if chosen. (reuters.com)

  • Shinjiro Koizumi — LDP reformist and current agriculture minister; formerly environment minister. (japan.kantei.go.jp)

Considerations

• The LDP lost its parliamentary majorities; coalition arithmetic or a unified opposition could, in principle, produce a non‑LDP PM. (reuters.com)

• A snap election is possible, but this market resolves on the first PM formally appointed after Ishiba’s resignation, regardless of whether a general election occurs beforehand. (reuters.com)