The Gaithersburg man suspected in the disappearence a Frederick woman while they were vacationing together in Aruba is suing to get $3.5 million from an insurance policy he took out on her, according to a court document.

Gary Giordano, 51, filed a lawsuit against AMEX Assurance Co. in Cook County, Ill., where the company has its headquarters.

Robyn Gardner, 35, vanished in Aruba in early August.

Giordano, Gardner's vacation partner, has denied wrongdoing and has claimed that she was swept away while the two were snorkeling. He was detained in Aruba for several months but was released in November.

According to the lawsuit, shortly before the Aruba trip, Giordano took out an insurance policy that covered Gardner. The policy provided for benefits of $3.5 million for accidental death and/or dismemberment. 

Giordano said Gardner is presumed dead and that he has asked AMEX to pay the policy, but the company has refused, according to the lawsuit. Giordano thinks AMEX believes it doesn't owe him any money under the policy.

An American Express spokewoman told the Associated Press that there's a 365-day waiting period to file these types of claims. Giordano told the AP that the lawsuit speaks for itself.

Last month, Giordano was arrested in Annapolis and charged with indecent exposure after he was found naked in a sport-utility vehicle with a woman, Anne Arundel County police said.