Griffin's hedge fund, Citadel, has been steadily selling Microsoft for the last year while buying shares of Taiwan Semiconductor.A good way to help develop your investment prowess is by looking at the actions of acclaimed money managers. Sounds easy, but how exactly can you do that?Well, luckily, the Securities and Exchange Commission requires institutional investors managing over $100 million to file a form 13F once per quarter. You can think of a 13F as an itemized receipt, breaking down each trade Wall S ...