Citi (C) Dec 26 calls are the most active equity options contracts in the first 15 minutes of trading Tuesday. 6,300 changed hands. The top trade is a 1214-lot for $1.32 when the market was $1.30 to $1.33. Dec 30 calls on Citi are seeing interest as well. 1,025 traded. Shares are up 20 cents to $25.20 and total volume in the bank is 13,000 calls and 4,525 puts. Prior to today, shares lost ground in seven of the past nine trading sessions and gave up 20.4 percent. Implied volatility in Citi options has eased 2.5 percent to 62.5 today and the flow seems to refllect expectations for a recovery of some of the recent losses in the weeks ahead.

Sirius Satellite (SIRI) with relative strength and high call volume today. Shares are up 7 cents to $1.85 and options volume on the satellite radio operator is 31,000 calls and 1,700 puts. The top trade is a 951-lot of Jan $2 call at the 8-cent asking price. 9,706 traded. Dec and Jan13 $2 calls are the next most actives. Looks like upside call buyers dominating the flow in SIRI today and implied volatility in the options on the stock has eased 2.5 percent to 51.5. Only headline on the stock today is news that Ozzy is launching his own Sirius channel.

*Scanning all single-stocks subject to 2500 contracts minimum call or put volume

Heavy trading in Focus Media (FMCN) is being attributed to a negative Muddy Waters research report (unconfirmed). Shares are down $7.40 to $18.10 and today’s options volume, of 75K puts and 24K calls, is 5X the daily average for the Chinese media company. Jan 25, Dec 17, Dec 20 and Jan 12.5 puts are seeing heavy trading at the offer. April 30 calls are the most actives. 10.7K traded. Meanwhile, implied volatility in FMCN optoins jumped 50 percent and is elevated at 133.5.

*Scanning all single-stocks subject to 2500 contracts minimum call or put volume

Gilead Sciences (GILD) falls to a new 52-week low and is down $4.62 to $35.27 after the company announced plans to acquire Pharmaseet (VRUS) for $137 in cash. Shares are down and one strategist seized the weakness to initiate a Jan 38 – 41 (1X2) call raito spread for 48 cents, 1100X on AMEX. Looks opening and buyer-initiated. The next biggest trade in GILD today is a Jan 36 – 39 call spread for $1.23, 1000X. 20,000 calls and 5,900 puts now traed in GILD and implied vols jumped 55 percent to 41.