Soros’s biggest holding? A bearish call on the S&P 500 August 15, 2013, 5:11 AM It’s 13F revelation time, and the headlines are full of news about big investor George Sorosgoing hot for Apple and dumping on gold in the second quarter. However, there’s something else in those numbers that should make investors sit up a little. Possibly buried amid the Apple excitement is the fact that Soros Fund Management’s biggest position is a put on the S&P 500 ETF SPY . Soros bought a put on 1,248,643 SPY units in the quarter. A put option gives the owner the right to sell a specific amount of an asset at a set price within a set time, and generally means the investor expects that asset will go down in price. So yes, as Bullion Baron and Whalewisdom point out, Soros is making a huge bet on the S&P 500 SPX  going lower. Doing the calculations, the Baron points out that the SPY put position — relative to the total size of the fund — rose from 1.28% to 4.79% in the first quarter, more than tripling. It also went up 13.54% in the second quarter, nearly tripling again. History has a story to tell about big calls from Soros and people should be paying attention, says the Baron blog: “Soros reportedly made $1 billion betting against the British pound in 1992. We heard rumors of Soros making a $1 billion bet against the AUD (a position that has done well if true). We heard when he made $1 billion betting against the yen. Where are the headlines for his $1.25 billion bet against the stock market?” asks Baron. Soros is clearly picking and choosing, with his doubled position in Apple AAPL +0.03% and a call on J.C. Penney  JCP   shares. He also dumped chunks of CitigroupC -0.14% and Netflix NFLX  in the second quarter. But deciphering what Soros was thinking when he upped that SPY put position is not so easy. As Baron notes, we don’t really know the precise structure of target dates and holdings. The fund could have increased that SPY put anytime in the second quarter. Joseph from the Baron further said this when asked about the significance of Soros’s move: “The last time SPY puts topped the Soros Fund was in the 30th June 2011 filing and we saw the S&P 500 lose 15%+ over the 6-7 weeks following, over July/August (during which time Soros reduced the position substantially). The position in 2011 was less than half the size of the current one which makes me think he might be anticipating a larger decline on this occasion.” Looking back on how the S&P 500 performed in the period, the index closed out the quarter with a gain of 2.4%, even as the month of June posted a loss amid worries about when tapering would begin. The quarter so far is already looking better than the last, with the S&P 500 up nearly 5%. We may need to wait another quarter to see how Soros is really feeling about the market. As George has said himself: “Markets are constantly in a state of uncertainty and flux, and money is made by discounting the obvious and betting on the unexpected.”