Ivanhoe Mines (IVN) is under pressure today and options on the stock are actively traded after Rio Tinto won an arbitration process involving the company, but said it has no plans to make a full takeover offer for Ivanhoe. IVN lost 16 percent to $17.39 on the news. Options volume on the Vancouver-based miner is 18,000 calls and 7,100 puts. Interestingly, the top trade is a 2377-lot of Mar 20 calls for $2.15 per contract on ISE, which is an opening buyer, according to data from the exchange. 5,070 now traded. Jan 17.5 puts, Jan 25 calls, Jan 19 calls, Jan 16 puts, Dec 17 puts and Mar 19 calls on IVN are actively traded as well and implied volatility is down 18.5 percent to 83, now that this company event-risk has now passed.