Carl Icahn, a New York native who dropped out of medical school and became a Wall Street billionaire, is known for taking large holdings and pushing for change in those companies. Icahn is popular for forcing change at companies as diverse as Texaco, RJR Nabisco, and Imclone.

Icahn Capital was valued at $6.24 billion across 24 holdings as reported for the last quarter, which ended March 31. Icahn has been heading the fund since its inception in 2004, although his investing career dates back to 1961.

Earlier this year, Icahn announced that he would be returning nearly all outside investors' money -- 95% -- by April 30. Outside investors accounted for $1.76 billion of the fund's assets. Icahn wrote to those investors, saying that he did not wish to be responsible to investors if another crisis were to hit.

Icahn's portfolio
At the end of each financial quarter, hedge funds overseeing more than $100 million must file a 13-F with the Securities and Exchange Commission, publicly disclosing their stock positions. There can be valuable information hidden within the piles of documents and we have partnered with AlphaClone to bring it to you. Though the 13-F illuminates long stock bets, it does not give any information on what these hedge funds may be shorting or any inter-quarter trades.

In the quarter ended March 31, Icahn Capital increased its stake in Lawson Software (Nasdaq: LWSN) by 5.1%. The fund also added 6.6% to its holdings in Hain Celestial (Nasdaq: HAIN). Let's dig a little deeper on these two.

Lawson Software
The $1.8 billion Minnesota-based company designs software to improve the operations and planning of companies to improve profitability. The company announced April 26 that it had agreed to go private, accepting a takeover bid. Lawson stockholders will receive $11.25 per share in cash in the transaction valued around $2 billion. According to company documents, the transaction is expected to be completed by the third quarter of 2011. Icahn first started buying shares of Lawson last April and has become one of its largest shareholders; Capital IQ reports that he owns just less than 11% of the company's outstanding shares.

Hain Celestial
The company produces natural and organic food products and personal-care products, with more than 15 renowned brands. For its most recent quarter, Hain announced strong earnings of $16.8 million, a big increase over the $2.7 million in net income from the same quarter in 2010. Icahn has been adding to his Hain stake since the first quarter of last year.

Other notable portfolio moves include a slight drop in the Motorola Solutions (NYSE: MSI) holding and the addition of Motorola Mobility (NYSE: MMI). In early January, Motorola broke itself into these two companies. After the spinoff of Motorola Mobility and a reverse split in the surviving Motorola Solutions, shareholders ended up with 1/8 of a share of Motorola Mobility and 1/7 of a share of Motorola Solutions for each original Motorola share they owned prior to the moves.

In addition, Icahn continues to push for change. Last month, Mentor Graphics (Nasdaq: MENT) announced that shareholders had elected five management director nominees and three of Carl Icahn's nominees. At a market value of about $1.4 billion, this company looks to optimize and help find solutions for companies that develop electronic products. In March, the stock for the Oregon-based company was trading around $15; it currently trades around $12.60.

Here's a look at Icahn's top 10 reported holdings, and the associated share-count changes in each holding:

  1. Motorola Solutions -- reduced by less than 0.1%.
  2. Biogen Idec (Nasdaq: BIIB) -- no change.
  3. Genzyme -- no change.
  4. Clorox (NYSE: CLX) – new.
  5. Motorola Mobility – new.
  6. Lions Gate Entertainment (NYSE: LGF) -- no change.
  7. Mentor Graphics -- no change.
  8. Hain Celestial -- increased 6.6%.
  9. Lawson Software -- increased 5.1%.
  10. Amylin Pharmaceuticals (Nasdaq: AMLN) -- no change.

Icahn sold out of several stocks, including Masco, a building supplies company, and Navistar International, which manufactures parts for trucks and other large vehicles. Both stocks are down by double-digit percentages over the past three months.

Genzyme ceased existence as a stand-alone company right after the end of the first quarter. French pharma giant Sanofi purchased all outstanding Genzyme shares for $74 in cash and one contingent value right per share. (Icahn had waged a proxy fight last year and won two seats on the board.)

So there you have it -- the blow-by-blow of Icahn Capital's latest moves. Tell us what you think in the comments section below.

Company data provided by AlphaClone LLC, a San Francisco-based research and investment-management firm that tracks hedge-fund public disclosures. For more information on the firm's investment approach, visit AlphaClone.

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