Berkshire Hathaway's second-quarter 13F is expected after Thursday's close, consistent with Buffett's habit of filing on the 45-day deadline. The filing will show investors which stock positions Berkshire Hathaway decreased and increased in the quarter. The filing could also indicate whether Buffett and the Berkshire team invested in any new companies or completely exited from existing positions. Investors are also looking forward to potentially hearing what Berkshire's mystery stock purchase in the past se ...