Goldman Sachs analyst Heather Bellini downgraded Microsoft from Neutral to Sell (relative to their coverage) with a $27 price target (currently at $28.75, down $1.53 or 5%) due to a worsening PC trends and lack of traction in tablets and smartphones.
From: http://www.forbes.com/sites/chuckjones/2013/04/11/goldman-sachs-downgrades-microsoft-to-sell/