Latham & Watkins and Clifford Chance are negotiating with regulators across the world to get antitrust clearance for what is suddenly among the more controversial deals of 2009 — Oracle’s $7.4 billion proposed acquisition of Sun Microsystems.

Thomas Vinje, the Brussels-based Clifford Chance partner handling the antitrust work in the EU, may have the toughest job on the Oracle legal team. On Monday, the EU’s antitrust agency sent the company a letter of objection indicating it believes the deal may break antitrust rules, according to Bloomberg.