Rumors of insider trading surround Berkshire Hathaway’s (NYSE:BRK.B) deal to buy Lubrizol (NYSE:LZ) announced just yesterday, after analysis by Bloomberg showed call trading surged suspiciously on March 9th, 5 days before the deal was announced, to 2,931 contracts, far higher than Lubrizol’s 4-week average trade volume of 413. A single block of 2,168 April $110 calls traded for $2.35 each that day, their value surging 11-fold to $24.70 yesterday. The company’s common stock jumped 28% to $134.68. Ophir Gottlieb, head of client services at Livevol Inc., a San Francisco-based provider of options market analytics said, “That is more than suspicious. It looks like a naked purchase of calls, and that’s highly suspicious if not straight insiders trading.” Citigroup (NYSE:C) and Evercore Partners Inc. (NYSE:EVR) were the financial advisers to Lubrizol, while Jones Day was legal counsel. Munger, Tolles & Olson LLP was legal counsel for Berkshire.