Reuters: Yahoo shareholder Starboard Value said the company’s spinoff of its stake in Alibaba was a “good first step” but it could do more, including a share buyback of up to $4 billion. “Yahoo is in need of a major overhaul,” the activist investor wrote in a letter to Yahoo’s board. Starboard recommended that Yahoo aggressively cut costs, buy back $3.5 billion-$4.0 billion of shares and separate the Yahoo Japan stake in a tax-efficient manner.