Attorney General Christine Gregoire filed consumer-fraud charges yesterday against the owners of Thesaurus Fine Arts, a defunct Seattle store known to sell phony Asian antiquities.

The civil suit comes 13 months after a Seattle Times series, "The Art of Deception," exposed the Pioneer Square gallery, its owners, and two Hong Kong testing laboratories for certifying fakes.

The store was owned by Steven Ng Sheong Cheung, 68, a former University of Washington professor and renowned economist in China, and his wife, Linda Su Cheung, 57, according to the suit filed in King County Superior Court. Steven Cheung, who could not be contacted yesterday, had denied ownership.

He also had denied that his antiquities, some alleged to be more than 1,000 years old, were modern imitations. Scientific tests paid for by The Times and expert opinion proved the objects were fakes. The state attorney general's consumer-protection office also paid for outside evaluation, according to other buyers of Thesaurus objects who were in contact with the office.

"I'm not really able to talk about what we've done other than to say that we've substantiated it," Assistant Attorney General Cheryl Kringle said yesterday. The maximum penalty under the Consumer Protection Act is $2,000 per deceptive business act, if the charges are proven in court. Gregoire's office said there were "many" deceptive acts involved.

Reputable Seattle dealers say they complained for years to authorities about Thesaurus. Some dealers said they received letters from Thesaurus' lawyers that threatened legal action for making complaints.

Gregoire, who is running for governor, said in a news release, "This case highlights an important lesson for consumers who buy art, collectibles or antiques. Do your homework and beware of a deal that sounds too good to be true."

State investigators were unable to locate the Cheungs, Kringle said. The state served papers on Phillip Thom, a Seattle attorney and registered agent for two Cheung companies. Thom did not reply to phone calls and e-mail seeking comment yesterday.

The Cheungs, indicted last year for federal tax evasion, are believed to be living in Shanghai, China, which doesn't have an extradition treaty with the United States. The IRS alleges that the Cheungs concealed money through businesses including Thesaurus.

Steven Cheung, a naturalized U.S. citizen, lived in Seattle from 1969 to 1982, teaching economics.

Thesaurus Fine Arts opened in 1998 and also sold through eBay. The store closed when "The Art of Deception" was published and it never reopened. Some Asian-antique dealers and Pioneer Square gallery owners worried that the Thesaurus scandal would scare off buyers because the store had such a prominent location and legitimate appearance.

"Obviously there was concern, but I didn't see an effect," said John Fairman, owner of Honeychurch Antiques, a respected Asian-antique store now at 411 Westlake Ave. N.

Fairman just returned from a buying trip to China and Hong Kong and said the trade in fakes hasn't slowed. "You knock one bad guy down and another springs up in his place. There are always going to be people out there who want to sell fakes."

What made Thesaurus unique, Fairman said, was that nearly everything in the shop was intentionally misrepresented.

"The usual scheme is a little more subtle," he said. "There are shops that open where half the objects are fakes, where the dealers mix good and bad, and kind of shrug their shoulders when things go out the door."

Thesaurus also stood out for providing scientific certificates of authenticity on fakes. Many of the objects were certified by a Hong Kong testing laboratory that Steven Cheung helped establish or by a university lab he frequently hired.

A City University of Hong Kong lab that issued false certificates of authenticity for Steven Cheung recently announced it had met guidelines from the International Organization for Standardization.

The lab director, professor Po Lau Leung, has certified more than 600 ceramic items in the past 10 years, many of them for Thesaurus.

But The Times' experts said the objects they tested were made recently.

Leung explained away the contradictory test results by saying the ceramic objects he certified had been re-fired. Other laboratory directors discounted that claim.

Fairman said the good news from the scandal is that the public is better informed.

"The trend in the business is that people are asking more questions," he said.

Because art fraud can be tricky to prove and prosecute, disreputable dealers often get by with little public scrutiny except word-of-mouth by unhappy buyers.

"People who knew Thesaurus were very pleased it was no longer there, corrupting the trade in Pioneer Square," said John Stevenson, a local Asian-art expert.

But even though Thesaurus has closed down, it's easier than ever to sell fake antiques online, Fairman said.

Deceptive dealers can operate easily from anywhere in the world with nothing but a computer, a promise, and a lot of gullible buyers keeping them in business.

The Internet "is almost tailor made for fraud," Fairman said.

Duff Wilson: 206-464-2288 or dwilson@seattletimes.com. Sheila Farr: 206-464-2270 or sfarr@seattletimes.com