Biogen Idec has confirmed that a second representative from dissident shareholder Carl Icahn's slate of directors has been elected to the board.

Richard Mulligan will join fellow Icahn nominee Alexander Denner, meaning that two of the billionaire investor’s choices, out of a slate of four, have secured a seat on the board. The announcement comes a week after Biogen’s annual meeting was held which was marked by controversy over the voting procedure used by the company.

This led to accusations of vote-rigging from the Icahn grouping and threats of a lawsuit after Biogen delayed the count. However on the surface everything seems to have been sorted out and the company’s chairman Bruce Ross, said “we welcome Alexander Denner and Richard Mulligan to the board and look forward to working with them to build on [the company’s] strong track record of delivering value”.

All this means that Mr Icahn, who owns a 5.6% stake in Biogen, will now be in a better position to forward his proposals for the firm. Chief among those is a proposal to split the company into two, with one firm focusing on neurology and the other on cancer. Mr Icahn has argued that "separating Biogen assets will enhance shareholder value as management focus should improve and disparate assets appeal to different buyers".

The investor has been at loggerheads for some time with the management at Biogen, having lost out in a proxy battle last year against the firm. At the beginning of 2008, Mr Icahn had criticised the board for not looking hard enough to find a buyer and its decision to take down the ‘for sale’ sign in December 2007 after no serious offers were made.

The latest proxy battle is a victory for Mr Icahn although Biogen noted that shareholders rejected his proposal to move its state of incorporation from Delaware to North Dakota and to cap the size of the company’s board at 13 people.