Mizuho Financial Group shares rise 6.39% after-hours on analyst upgrade and buyback plan amid strong rally.

Mizuho Financial Group surged 6.39% in after-hours trading following a Bloomberg report indicating the firm was upgraded to "Buy" by analysts, citing improved valuation metrics and strategic share buyback plans. The firm's recent 5x gain and a multi-month rally in share price, coupled with renewed investor interest in Japanese financials amid a broader Nikkei rebound, further fueled the momentum. Analysts highlighted the buyback potential as a catalyst, while a Yahoo Finance article emphasized Mizuho's valuation re-rating after sustained positive performance. The stock's rally aligns with broader market optimism and active institutional coverage, though specific earnings or operational data were not disclosed in the cited news.