Although it has slid back almost 2% today, Penn Virginia Corporation (NYSE:PVA) is still up more than 10% following George Soros’s letter filed with the Securities and Exchange Commission (SEC) yesterday. While the implications of the letter, that Soros is gearing up for an activist campaign, was lost on no one outside investors are tipped to what Soros believes he can accomplish by the short dated options that he holds on PVA. $17 strike price shows that Soros thinks Penn Virginia still undervalued Soros currently owns 9.18% of Penn Virginia Corporation (NYSE:PVA), making him the company’s largest shareholder, but he…