At a time when hedge funds are facing tremendous pressure to bring in big returns, few have been able to meet investor demand. But billionaire Ken Griffin's investment firm Citadel Advisors has been one of the few funds to impress over several recent quarters. (See also: Tough Times fo�🉐�r Citadel's Ken Griffin: Only $600 Million in Profits In 2016.)

Citadel's 13F filing for the fourth quarter of 2017 reveals that Griffin was once again able to outpace the 澳洲幸运5官方开奖结果体彩网:S&P 500 in the final months of 2017. This t♋ask has become increasingly difficult for many hedge funds. The list value of Citadel Advisors' stock holdings was up by 18.5% as compared with the previous quarter, while the S&P 500𝔉 Index gained only 6.1% for the same period, .

Positions In Amazon and Facebook

Griffin's largest position for Q4 was in SPDR S&P 500 ETF (SPY), a position of more than $18 billion and constituting nearly 12% of C🦋itadel's total portfolio. The next largest positions represent a significant drop-off in terms of size and percentage weight in the portfolio.

Coming in second place was Amazon.com Inc. (AMZN). Citadel owned $5.6 billion in AMZN shares by the end of Q4, representing about 3.6% of the firm's total holdings. Third place was Facebook Inc. (FB), a position of $3.1 billion and 2.0% of t𝓀he total holdings.

The next largest positions were in IShares (IWM), Invesco QQQ (QQQ), Alphabet Inc. (GOOG), and Alibaba Group (BABA). In total, these seven positions represented just under 🌳one-quarte🀅r of Citadel Advisors' total portfolio.

Biggest Buys Include SPY, BABA, and FB

Aside from being the largest single position in Citadel's stock holdings, SPY also represents the largest purchase for Q4. Ken Griffin bought up $6.1 billion in SPY shares during the last three months of 2017. He also bought more than $1 billion each of BABA, FB, and Bank of America Corp. (BAC). Acc☂ording to the 13F report, the fund's total holdings in stocks 🀅were $154.4 billion, as of December 31, 2017.

Compared with the size of the purchases over Q4, Citadel's biggest sells were relatively small. The largest sale was for Goldman Sachs (GS). Griffin sold of more than $440 million in stock for the bank. He also sold off more than $324 million in Apple Inc. (AAPL) stock. The third-largest sell was for Fidelity (FIS), a sale of $284.5 which marked a liquidation of Citadel's position. (See also: Hedge Funds Bet on Consum♍er Discretionary Stocks in Q4: 13F.)

The 澳洲幸运5官方开奖结果体彩网:U.S. Securitie𝔍s and Exchange Commission (SEC) requires 13F reports from all hedge funds managing at least♐ $100 million. These filings are due 45🌱 days from the end of each quarter and are available to the public. While 13Fs can be a useful window into how major investors focused their efforts in the previous quarter, they are necessarily outdated by the time they become available to the public, making them unreliable as tools for investment.