A former executive at Bristol-Myers Squibb faces up to 20 years in prison and a possible $5 million fine after admitting to insider trading linked to the drugmaker's acquisition targets.

The Federal Bureau of Investigation says that Robert Ramnarine, 46, has pleaded guilty to security fraud in a New Jersey court. He was employed by B-MS from 1997 to August 2012 and from March 2008 on, he held a variety of high-level, executive positions.

Those included top roles in pensions and saving investments and latterly he was assistant treasurer for capital markets. As a result of these positions, Mr Ramnarine was involved in evaluating potential acquisition targets for B-MS and was privy to inside company information which he was legally banned from disclosing.

However during May and June 2012, he traded on material, non-public information regarding B-MS' anticipated acquisition of Amylin Pharmaceuticals, which enabled him "to reap substantial profits by engaging in lucrative trading in stock options of Amylin shortly before BMS announced its plans" to buy the latter in late June last year.

As part of his plea, Mr Ramnarine admitted to $311,361 in illicit gains made from trading in stock options of not only Amylin but also several other B-MS acquisition targets, such as ZymoGenentics and Pharmasset. B-MS submitted a bid for the latter firm through a confidential auction process, but it was subsequently acquired by Gilead Sciences.