The Seoul Central District Court recently held that an e-commerce seller selling computer program product keys without authorization was liable for aiding and abetting copyright infringement.

In this case, Microsoft, the maker of the ubiquitous Windows computer operating system ("Plaintiff"), distributed free Windows 10 license keys to students participating in its educational support program. The Defendant somehow obtained these product keys, and then sold them to consumers through an e-commerce platform without the Plaintiff's authorization. The Plaintiff eventually filed a complaint with the Seoul Central District Court asserting copyright infringement and seeking an injunction against Defendant continuing to sell and distribute Windows license keys.

An earlier Supreme Court case involved a defendant who posted the serial number of a computer program on his personal website without authorization, in which the Supreme Court held that duplicating and distributing a computer program's serial number is not an act of infringing the copyright on the computer program itself, because serial numbers are simply a technical safeguard to ensure legitimate installation or use of the relevant program. However, the Court reasoned in that case that if a third party then reproduces the program using an improperly posted serial number, thereby infringing the copyright on the program, the defendant's duplication/distribution of the serial number can be considered aiding and abetting of the third party's copyright infringement (Supreme Court Decision No. 2001Do2900 dated June 28, 2002, et al.).

Consistent with the above, the Seoul Central District Court ruled that the Defendant's sale of the product keys in this case was not itself infringement of the copyright on the Windows software, but did constitute aiding and abetting copyright infringement by others. This is because the Defendant sold product keys to consumers on the general market who were not licensed by the Plaintiff, and these unlicensed purchasers then used the product keys to install and use the Plaintiff's copyrighted Windows software and thus infringe the Plaintiff's copyright.

This ruling confirms that copyright is available to makers and right holders of commercially-sold computer software seeking to enforce their rights against unauthorized sales of product keys or serial numbers for software.