As reported by New York Times, court documents were published on Friday that show that part of Twitter’s source code – the underlying software that makes the platform possible – has been leaked online.

According to court documents, Twitter claimed copyright infringement in an attempt to remove the code from GitHub, where it was hosted. Although the code was removed the same day, no information was provided on how long it remained available, nor on the extent and depth of the leak.

Twitter also sued to compel GitHub to reveal the identity of the user who posted the code, as well as those who accessed and downloaded it.

The NYT reports that, according to anonymous sources at the company, Twitter executives suspect it was the work of a disgruntled employee who quit “within the last year.”

Company executives who spoke to the NYT are primarily concerned that data obtained from the stolen code could facilitate future hacking attacks.