"We have invited the FBI several times to take a look around in Second Life and raise any concerns they would like, and we know of at least one instance that federal agents did look around in a virtual casino," said Ginsu Yoon, until recently Linden Lab's general counsel and currently vice president for business affairs.
Second Life is a popular online virtual world with and its own economy and currency, known as the Linden dollar, which can be exchanged for U.S. dollars.
Yoon said the company was seeking guidance on virtual gaming activity in Second Life but had not yet received clear rules from U.S. authorities.
The FBI and the U.S. Attorney's Office for Northern California declined to comment.
Hundreds of casinos offering poker, slot machines and blackjack can easily be found in Second Life. While it is difficult to estimate the total size of the gambling economy in Second Life, the three largest poker casinos are earning profits of a modest $1,500 each per month, according to casino owners and people familiar with the industry.
The surge in Second Life gambling coincides with a, which has arrested executives from offshore gambling Web sites.
Most lawyers agree that placing bets with Linden dollars likely violates U.S. antigambling statutes, which cover circumstances in which "something of value" is wagered. But the degree of Linden Lab's responsibility, and the likelihood of a crackdown, is uncertain.
"That's the risk; we have a set of unknowns, and we don't know how they're going to play out," said Brent Britton, an attorney specializing in emergent technology at the law firm Squire Sanders & Dempsey in Tampa, Fla.
Britton said Linden Lab could face criminal charges under the 1970 Illegal Gambling Business Act or the Unlawful Internet Gambling Enforcement Act. The latter law, passed last year, takes aim at credit card companies and other electronic funds transfers that enable Internet gambling.
"What they did was go after the processors, and made it a crime to process payments that relate to online gambling sites. Linden could potentially be held as the same sort of processor," said Sean Kane, a lawyer at New York's Drakeford & Kane who has studied the legal issues of virtual worlds.
"If you're buying money on the Lindex (a virtual currency exchange) and utilizing it for gambling purposes, Linden could have a much higher level of responsibility," he added. "If they would be found in violation, that's difficult to say, but I can see a much stronger case being made."
Linden Lab's rules prohibit illegal activity.
"It's not always clear to us whether a 3D simulation of a casino is the same thing as a casino, legally speaking, and it's not clear to the law enforcement authorities we have asked," Yoon said.
Even if the law were clear, he said the company would have no way to monitor or prevent gambling in Second Life.