Portola Pharmaceuticals, Inc. Information Request Form

Levi & Korsinsky, LLP has commenced an investigation into the fairness of the sale of Portola Pharmaceuticals, Inc. (“Portola” or the “Company”) (NASDAQ: PTLA) to Alexion Pharmaceuticals, Inc. (“Alexion”) (NASDAQ: ALXN). Under the terms of the merger, a subsidiary of Alexion will commence a tender offer to acquire all of the outstanding shares of Portola’s common stock at a price of $18 per share in cash.

The Portola merger investigation concerns whether the Board of Portola breached their fiduciary duties to stockholders by failing to adequately shop the Company before agreeing to enter into this transaction and whether Alexion is underpaying for Portola shares, thus unlawfully harming Portola shareholders.