Top hedge fund manager Ken Griffin sold Amazon and bought Palantir in the third quarter.Ken Griffin runs Citadel Advisors, the most successful hedge fund in history as measured by net gains since inception. Additionally, Citadel outperformed the S&P 500 (^GSPC +0.32%) by 8 percentage points over the last three years. That makes Griffin an excellent source of inspiration for retail investors.In the third quarter, Citadel sold 1.6 million shares of Amazon (AMZN +0.10%) and purchased 388,000 shares of Palantir ...