Hedge funds make fortunes by looking for unique ways to invest and having a strategy. At The Motley Fool, we value this approach. By tracking the buy and sell decisions of successful fund managers such as massive outperformer Mason Hawkins, we hope to gain insights into hidden opportunities in the market.

Every quarter, any fund managers overseeing more than $100 million must publicly disclose their quarter-end holdings through the Securities and Exchange Commission on a form 13-F. The filing lists all U.S.-traded securities the fund held at the end of the quarter. Although the form doesn't disclose short positions or intraquarter trades, it can illuminate long stock bets.

To better decipher this 13-F data, we turned to Motley Fool partner AlphaClone, a research and investment-management firm that develops investment strategies based on hedge funds' public disclosures.

Meet Southeastern Asset Management
Mason Hawkins has been the CEO of Southeastern Asset Management since 1975. He and his partner also manage the Longleaf Partners Fund, which has a 20-year cumulative return of 921.1% vs. 482.2% for the S&P500.

Hawkins, a University of Florida alumnus, founded his fund looking to invest in companies that had, "good business, good performance, and a good price." That's no easy task on Wall Street. To achieve its goal, the fund looks for companies with a market price no more than 60% of Hawkins' appraisal of their fair value. Hawkins sizes up businesses by studying financial statements, trade publications, and regulatory information, and talking to managers, competitors, and suppliers.

This strategy has richly rewarded the fund. As of March 31, 2011, Southeastern Asset Management was valued at $25.5 billion across 42 holdings. What purchases have powered Southeastern's appreciating portfolio?

News Corp. (Nasdaq: NWSA), which makes up 4.08% of the whole portfolio, rose significantly in value during the quarter. As most media companies struggle to adjust to a shifting competitive landscape, News Corp. has successfully diversified into cable programming, movies and television, direct broadcast satellite television, publishing, and other profitable pursuits.

Hawkins' fund also increased its holdings in Loews (NYSE: L) by 15.76%, which definitely helped the increase in overall portfolio value during the quarter. This diversified holding company encompasses five subsidiaries: CNA Financial Corp., Diamond Offshore Drilling, HighMount Exploration & Production, Boardwalk Pipeline Partners, and Loews Hotels. In 2010, Loews ceded its legacy asbestos and environmental pollution liabilities to National Indemnity Co. for $328 million.

In addition, Southeastern decided to invest in travel website Expedia (Nasdaq: EXPE). Hawkins added about 4.26 million shares to his fund's portfolio. During the quarter, Expedia signed a multiyear agreement to more directly book flights with U.S. Airways and partner with the airline to offer passengers additional ways to purchase extra seating options.

Finally, Southeastern began investing in Abbott Laboratories (NYSE: ABT), the broad-based health-care company with business in more than 130 countries. In the quarter ended March 31, Abbott increased its dividend by 9%, to $0.48 per share, and started numerous new tests for potential products worldwide.

Southeastern's 10 largest positions (by value) and associated changes as of March 31 were:

  1. Chesapeake Energy (NYSE: CHK) -- increased 25.4%.
  2. DIRECTV (Nasdaq: DTV) -- increased 8.1%.
  3. Dell (Nasdaq: DELL) -- increased 8%.
  4. Yum! Brands (NYSE: YUM) -- increased 2.6%.
  5. Aon (NYSE: AON) -- increased 14%.
  6. Cemex (NYSE: CX) -- reduced 14.4%.
  7. Loews -- increased 28.2%.
  8. Walt Disney (NYSE: DIS) -- reduced 19.1%.
  9. News Corp. -- increased 33.1%.
  10. Liberty Media (Nasdaq: LINTA) -- reduced 1%.

The fund eliminated its positions in Verizon Communications and Telephone & Data Systems.

How would you have performed following Southeastern Asset Management?
According to AlphaClone's backtest simulation, any Fool who invested every quarter since 2000 in Southeastern Asset Management's 10 largest holdings (at the time they were publicly disclosed) would have returned 94.2%. Including dividends, the S&P 500 returned only 12.7% during that same period. AlphaClone's simulation buys and sells the stocks disclosed in the 13-F five trading days after the SEC's filing window closes.

Highlights from Southeastern's portfolio this quarter include:

  • Current winner: Chesapeake Energy did well, increasing 29.4% in the first quarter of the year. The stock makes up 10.4% of the total portfolio, making it the fund's top holding.
  • Current loser: Cemex fell 13.3% in the first quarter of 2011. It accounts for 4.8% of the entire portfolio.

So there you have it -- the blow-by-blow of Southeastern Asset Management'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.

IMPORTANT DISCLOSURES FOR BACKTEST PERFORMANCE RESULTS

Backtesting is the process of evaluating a core strategy by applying it to historical data. Backtested performance results are provided for purposes of illustrating historical performance had a core strategy had been available during the relevant period. Backtested performance results are hypothetical and have inherent limitations. AlphaClone makes no representation that any core strategy will achieve performance similar to any backtested performance results. Actual results could differ materially from backtested performance, and future results could differ materially from backtested performance. Past performance is no indication or guarantee of future results.