Tesoro (P/C Chart, news, volatility) calls are actively traded. Shares are up 63 cents to $17.84 and 14K traded, compared to 2,504 puts. Feb 20 calls are the most actives. 9,200 traded and about half hit ask-side (20 percent mid-market). No news to explain the gains in the shares or the interest in TSO calls. Earnings due out Feb. 19, the day before the Feb contracts come off the board.