A quartet of leading US law firms have won key roles on Oracle’s controversial $6.3bn hostile bid for software rival PeopleSoft – securing a slice of what promises to be one of the most lucrative deals to hit the battered US M&A market in the past three years.

The aggressive bid, launched on 6 June, sees New York’s Davis Polk & Wardwell advising Oracle, with Skadden Arps Slate Meagher & Flom acting for the company’s financial advisers Credit Suisse First Boston.