LONDON (Reuters Breakingviews) - COMING TO GREF. Sberbank is struggling to find a good match. Russia’s biggest bank and social media group Mail.ru plan to break up their $1.6 billion joint venture, the Financial Times reported. The decoupling would be Sberbank’s second split with a major tech group: last year Chief Executive German Gref parted with search engine and ride-hailing group Yandex. A clash of cultures between the state lender and entrepreneurs doesn’t help. The $87 billion bank arguably needs Mail.ru more than the other way around. Gref wants 60% of Sberbank’s sales to come from “tech ecosystem” services like e-commerce and streaming by 2030, compared to just 2% last year. The bank’s 100 million customers should help, but achieving this organically is still a stretch. Given the culture clash, outright takeovers risk quashing targets’ entrepreneurial spirit and devaluing the acquisitions. If Gref wants his transformation to be successful, he’ll need to compromise more. (By Dasha Afanasieva)