So it would seem that the volume of put contracts today was about 7x daily average. Here are a few possible explanations. (i) A shareholder with a large long position in the stock is hedging his downside by purchasing puts. He knows news is coming that will significantly move the sp, either up or down, but he doesn't know which. So he's trading part of the potential gains upon good news in return for reduced losses if the news is bad. Possible, but not likely, since the call volume did not spike today - and our hypothetical shareholder would likely have written a large number of covered calls to pay for the puts; (ii) someone affiliated with the company recently acquired restricted stock and is concerned that the sp might fall before he can sell it. He and the derivatives desk of his bank or investment banker enter into a cashless European collar, which his counterparty is now hedging by buying puts. (iii) someone knows that bad news is coming and bought puts today.
