Jan 10 (Reuters) - Activist investor Bluebell Capital Partners has built a stake in Bayer AG and is pushing for a breakup of the German pharmaceutical and agriculture company, Bloomberg reported on Tuesday, citing sources.

UK-based Bluebell is also seeking an overhaul of Bayer's corporate governance, the report added. (Reporting by Shivani Tanna in Bengaluru Editing by Chris Reese)