The tech giant bought three Lighthouse AI patents and three patent applications related to capturing video and monitoring environments for security purposes, patent-tracking magazine IAM is reporting. Apple apparently bought the patents and patent applications sometime in late-2018, but the transaction wasn’t revealed until recently when the U.S. Patent and Trademark Office (USPTO) updated their ownership information.

Lighthouse AI was a small home security company that went out of business in December. The company sold a camera with 3D sensing technology to identify people. Artificial intelligence was added to the cameras to help users more easily sift through security footage to find clips of interest. The company’s three patents centered on depth-sensing and identifying objects in recorded video. Its patent applications centered on communication and sharing security incidents with users.

Terms of the deal are unknown. Apple often makes small acquisitions to buy companies or their assets that ultimately become a feature in other products the tech giant already sells. It’s possible it could be doing the same with the Lighthouse AI patent portfolio.

It’s also possible that Apple has ambitions in the home security market. Two of its biggest competitors—Google and Amazon—offer home security products already and Apple might want to join that fight.

Apple did not immediately respond to a Fortune request for comment.