Two big trades in the options market caught the attention of traders today and provided some interesting insight into two different trading strategies.

Compaq

(CPQ)

and

CBS

(CBS) - Get Report

each saw single trades of more than 10,000 contracts in their front-month options as two large institutional investors took in premium by selling options 10 days before this month's expiration. The investors hope may be that neither stock moves much before the March 19 triple-witch and they can take their premiums to the bank.

On the

American Stock Exchange

, an investor sold about 10,000 CBS March 37 1/2 calls at the halfway point in the session.

The source of the big print was likely a large institutional investor pulling the trigger on a buy/write strategy through

Goldman Sachs

, suggests Wayne Wu, a trader for specialist

Kalb, Voorhis

in the CBS pit at the

American Stock Exchange

.

The trader sold the call options for about 9/16, ($56.25) per contract, taking in about $562,500 in premium, according to Wu. Goldman itself bought about 3,000 of the contracts for its own account, and the remaining 7,000 were sold to the crowd.

Buy/write is a term used to describe a trade in which an investor buys the underlying shares of a stock and sells calls against the position to defray the expenditure.

Wu speculated that despite the size of the trade, it was merely an exercise in taking in some premium and not a demonstration of any bearish sentiment about the stock. "There's no news on the stock," he adds. "I think the plan was to write some calls against a large stock position and take in some premium."

CBS's stock was down slightly to 36 3/8, dipping 5/16, this afternoon.

Compaq also saw a 10,000-contract trade print earlier in the session, but it was on the put side of the aisle. The big trade came in Compaq's March 30 puts, which were almost three dollars out of the money as the stock was dropping today. Compaq's stock was down 1 1/2 to 33 7/8 this afternoon.

The player involved in the trade was a institutional client selling the puts at 1/4 ($25) per contract, and taking in about $250,000 in premium, according to Mike Ditzler, an independent market maker in the Compaq pit on the

Pacific Stock Exchange

.

Since the investor didn't take in much premium, this play may be a chance to get some of the shares he sold back if Compaq falls below 30 and the puts get assigned, says Ditzler, adding that some large investors have been selling the stock in recent days.

That strategy would give the investor that chance if the stock falls below 30 by expiration. Since the investor sold the puts, if the stock goes below 30 by expiration, he would be obligated to buy the stock at 30 from those investors who bought the puts today.

"He obviously feels comfortable paying 30 for this stock," Ditzler says. If Compaq doesn't fall below 30 by expiration, the options expire worthless and the investor keeps the premium he took in today.

Goldman Sachs also acted as the broker on this deal and bought 5,000 of the put contracts for its own account, Ditzler says. The remaining 5,000 put contracts were sold to the crowd.