NEW YORK : Investors are watching quarterly filings on Wednesday to get a glimpse at how some of the world’s biggest money managers were positioned at the end of the second quarter, a period marked by a series of record highs in the S&P 500 that preceded a more recent bout of turmoil in U.S. stocks. Filed at the end of each quarter, the 13-F filings are one of the few ways to get a snapshot of how often-secretive market participants such as hedge funds and sovereign wealth funds are positioned,