Acorda (ACOR) options were among the most active Thursday, with 14,407 calls and 10,095 puts trading. Around 28% of calls traded offer side with 53% bid side, and 31% of puts traded offer side and 35% bid side. Net premiums on the day was -$404,000 so you can see the favor of volatility sellers as the 30 day implied fell 32.8% to 47. The largest trade of the day was a purchase of the December $22.50/$25 strangle for 1,275 contracts at a cost of $2.40 (open interest suggest a new trade was opened.) January $25 calls traded more than 5,500 contracts with sellers accounting for most of the action. The reason for the volatility selling was the FDA’s decision to extend the review date of its key MS Drug by 3 months, and obviously one trader feels an early decision could come in December.