Sequoia Capital's Thursday was a great day, as it goes for venture capital firms, as two of its companies -- LinkedIn, and Clearwell Systems, had exits. Sequoia's biggest gain was via the huge IPO of LinkedIn, which more than doubled its initial IPO on the New York Stock Exchange as LNKD. Sequoia's stake in LinkedIn is was worth more than $1.58 billion, based on its closing price. Sequoia owns 17.8 percent of LinkedIn. Clearwell Systems, also backed by Sequoia, was sold to Symantec for approximately $390M, with Sequoia and its fellow investors only putting $33M into the Clearwell.