PWCC Marketplace, a Lake Oswego company that sells sports cards on eBay, says it is working with law enforcement to investigate apparently altered cards sold through its service.

“We are not disappearing or burying our heads in the sand about this,” the company said in a statement Sunday posted to online bulletin boards, including Blowout Forums. “We are presently working with PSA (a third-party sports card authentication service) and law enforcement to ensure that all affected cards are brought to light and this information makes its way to our customers.”

Sports card collectors treasure pristine collectables without damage or scuffs. Vintage cards can sell for hundreds of thousands or even millions of dollars apiece if they’re in perfect condition.

That creates an incentive for sellers to clean up their cards, sometimes by trimming the edges to eliminate wear. Collectors revile the practice, which alters the original cards. In 2015, a sports memorabilia auctioneer was sentenced to 20 months in prison after he admitted trimming an especially rare Honus Wagner card.

Collectors have been buzzing in recent weeks about similar allegations over cards sold by PWCC, which moved from the Bay Area to Lake Oswego five years ago. The company is a major player in the trading card industry, working with prominent collectors including Arizona Diamondbacks owner Ken Kendrick, and was in the process of developing financing for collectors to buy cards and secure storage for collections.

In Sunday’s statement, PWCC said it will no longer sell cards from a dealer implicated in the allegations.

“We understand that we are responsible for our part in this mess,” the company said. PWCC said it “will do all that we can to make it right.”

In a separate statement Monday, PWCC acknowledged that a seller has been “using our platform to facilitate or sell altered cards.”

The company declined to say when it became aware of the altered cards on its marketplace, how many cards are involved, or what law enforcement agencies it is working with.

"We are redoubling our efforts to ensure any attempted sale of altered cards is detected and blocked prior to auction,” PWCC said.

-- Mike Rogoway | twitter: @rogoway | 503-294-7699