Berkshire Hathaway's (BRK.A 1.25%) (BRK.B 1.35%) portfolio has changed significantly over the past year, even though billionaire investor and company CEO Warren Buffett hasn't exactly been loading the company's portfolio with stocks. Investors have been taking note of Buffett's seemingly conservative investment strategy and what it might mean. Here are some of the most notable changes in Berkshire's portfolio this past year, and what, if anything, investors should read into these moves. Apple's presence in ...