Many hedge funds are drastically underperforming the markets this year. In fact, since 2004, the majority of hedge funds have underperformed the broader markets, despite the huge bull market in stocks.

Since most hedge funds get paid based on their returns for the year, managers who don't want to underperform often turn to shareholder activism as a way to increase shareholder value and ultimately boost their returns.

At Stockpickr, we track many of the latest activist situations. We highlight a few here.

Activist hedge fund

Harbinger Capital Partners

has purchased a 5.9% stake in starch goods company

Corn Products International

( CPO). Harbinger disclosed that it owns about 4.34 million shares of Corn Products.

Corn Products has a forward P/E of 13, a PEG ratio of 1.5 and quarterly earnings growth of 29%. The corn refiner also recently boosted its 2008 profit guidance and reported a 29% rise in first-quarter profit. Keep an eye on this one.

Another stock to watch is biotechnology company

Biogen Idec

(BIIB) - Get Biogen Inc. Report

. Billionaire activist investor

Carl Icahn

filed a proxy document on Friday to nominate three directors to Biogen's board of biotechnology.

Icahn, who has claimed that Biogen sabotaged an auction to sell itself, is nominating Alexander Denner, managing director of his Icahn Partners investment vehicle; Richard Mulligan, professor of genetics at Harvard Medical School; and Dr. Anne Young, head of the neurology service at Massachusetts General Hospital, to become Biogen directors.

Icahn also is pushing for

Enzon Pharmaceuticals

(ENZN)

to sell itself.

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The pharmaceutical company is definitely worth watching. In addition to Icahn's push, DellaCamera Capital sent a letter to Enzon in which the activist hedge fund said it is unhappy with the compensation granted to Enzon Chairman and CEO Jeffrey Buchalter. DellaCamera further called for the resignation of Goran A. Ando, Rolf A. Classon and Victor P. Micati, all members of Enzon's compensation committee.

Next on the list is

Circuit City

(CC) - Get Chemours Co. Report

. Dallas-based hedge fund HBK Investments is urging Circuit City to allow due diligence by

Blockbuster

( BBI), following Blockbuster's acquisition proposal. HBK also urged Circuit City's board to create a competitive bidding process in order to maximize shareholder value.

It is worth pointing out that Circuit City has a 22% short position.

Last on the list is

Applied Biosystems Group

(ABI)

. Steven Cohen of

SAC Capital

sent a letter to Applied Biosystems suggesting a sale of the company. Cohen said that his fund encouraged the company's board to take a number of actions and to explore all strategic alternatives.

For more activist ideas, please check out the

Latest Activist Situations

, a Stockpickr portfolio that tracks the latest activist situations recorded by the StreetInsider.com 13D Tracker.

You can also check out the latest activist filings from

Barron's

, a list we update every Saturday.

Stockpickr is a wholly owned subsidiary of TheStreet.com.