noun
wholly-owning parent company; full parent company; sole parent company
Legal and financial term for a parent company that owns 100% of a subsidiary's shares. Used in corporate law, M&A, and consolidated accounting contexts.
完全親会社は子会社の全株式を保有している。
The wholly-owning parent company holds all shares of the subsidiary.
この合併により、A社はB社の完全親会社となった。
Through this merger, Company A became the sole parent company of Company B.
Compound of 完全 (kanzen, 'complete') + 親会社 (oyagaisha, 'parent company'). The term is a direct calque from English legal/financial terminology.