How do you fight an activist investor breathing down your neck? By getting another large investor on your side. Fighting fire with fire, if you will.

Carl Icahn's chances to join the board of Genzyme (Nasdaq: GENZ) are becoming slimmer by the week. Last week, two of his four nominees were called out for also being on Biogen Idec's (Nasdaq: BIIB) board, which may violate antitrust laws. Now Genzyme seems to have dealt another blow to Icahn by bringing Ralph Whitworth, head of Relational Investors, on board.

In January, Genzyme struck a deal with Whitworth, offering a board seat this November in exchange for Whitworth's support of the company's nominees at the upcoming shareholder meeting. I guess Genzyme didn't think that was enough to win shareholders' support and decided to give Whitworth a seat on the board now, along with being allowed to approve the nomination of another independent director.

Whitworth will chair a new Strategic Planning and Capital Allocation Committee. You'll recall that Genzyme's failures and the reason why investors big and small are upset with the company have to do with its manufacturing plants. A contamination and a separate issue with filling drug vials have led shares to fall 37% from their high in 2008.

Interestingly, according to The Wall Street Journal, Whitworth tried to act as an intermediary between Icahn and Genzyme and offered to propose a director amenable to both sides, but Icahn refused because he wanted more seats. The continued pressure from Icahn appears to have led to the expanded power for Whitworth.

Icahn looks to be losing the battle, assuming the new outside leadership is enough to persuade investors to stick with management for another year. But he may have won the war.

Sometimes it's necessary for activist investors to take over the board as Icahn did with ImClone Systems, eventually getting Eli Lilly (NYSE: LLY) to outbid Bristol-Myers Squibb (NYSE: BMY) for the biotech. Other times the pressure is enough to get changes made. Icahn's threat to nominate board members was enough to get MedImmune sold to AstraZeneca (NYSE: AZN).

Turnarounds can be tough, and only time will tell if Whitworth plus Genzyme can get the job done. But whether they succeed or fail, it's clear that Icahn got the ball rolling.

If you're interested in picking through the wreckage for possible turnaround candidates, you should have the Inside Value team on your side. Check out the newsletter for free with a 30-day trial

Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool has a disclosure policy.