Twitter announced a new company policy on Tuesday that will help curb the spread of patent trolls and hopefully protect innovation. The microblogging site will no longer allow its patents to be used for offensive litigation, unless the plaintiffs have permission from the patents’ developers.

On its official blog, the company wrote: “It is a commitment from Twitter to our employees that patents can only be used for defensive purposes. We will not use the patents from employees’ inventions in offensive litigation without their permission.”

Twitter says that this policy will apply to its patents even after they sell them. This is a nice promise, but it might be a little premature, as MSNBC reports that Twitter does not currently have any patents.