While customers can already waltz into GameStop and purchase a used copy of Halo 3 or Black Ops, PC gamers are left out of the secondhand market -- they're lucky to even have a few shelves for actual new titles. But the nation's largest games retailer, which makes the bulk of its revenue from the secondhand market despite the disapproval of publishers and developers, is looking to change all that by selling used digital games, or rather, pre-owned license keys.

"It’s very interesting," said GameStop CEO Paul Raines in a recent interview. "There are some technologies out there in Europe, and we’ve looked at a couple that are involved. We’re interested; it’s not a meaningful business yet. Right now we’re not seeing that as a huge market, but I think we’re on the leading edge. There are a few companies, a few startups, out there that we’ve talked to that are doing this."

Naturally he wouldn't reveal who those outfits are, only adding that "we wouldn’t want to disclose that and have our competitors rushing in."

The move to selling previously-owned serial numbers isn't surprising as the industry is slowly shifting into a digitally-focused distribution model. Publishers will likely stick with physical media for years to come, but eventually consumers will reach a point where it's easier to purchase and download titles directly to their desktop, console or tablet. Used digital sales will also keep that aspect of GameStop's revenue flowing as physical media begins to fade away.

Earlier this month, a European court ruled that content creators cannot prohibit post-purchase redistribution of work no matter what the end-user license agreement claims (pdf). The ruling stemmed from a case between hardware and software producer Oracle and German company UsedSoft, the latter of which made a living purchasing and reselling software licenses from consumers. Obviously, UsedSoft won.

According to the court's judgment, a software author's exclusive license to distribute a given copy of its product is exhausted in the initial distribution. Thus, owners of the software can sell said copy without the author's consent. The judgment applies both to future end-user license agreements and preexisting ones.

By selling pre-owned digital games, GameStop could be entering new territory in regards to offering non-gaming software on the cheap. What that would include -- whether it's an unused Windows 8 key or a previous owned Office 2013 key -- is mere speculation at this point.