It looks like Google isn’t out of the antitrust hot water just yet. Bloomberg’s sources claim that the Federal Trade Commission is in the early stages of an antitrust investigation into Google’s business practices with Android, its popular mobile operating system.

FROM EARLIER:Surprise: Rose gold iPhone 6s appears to be the most preordered new iPhone

While the bare bones of Android are completely open source, not every part of Android can be used by anyone free of charge. If a device manufacturer wants their device to have access to the Google Play app store and Google’s app ecosystem, they have to pay Google licensing fees.

What does this have to do with antitrust law, you ask? It seems that making device manufacturers bundle Google’s own apps on their phones as a precondition for getting Google Play on their phones could be legally problematic.

“The practice of bundling products and services together may violate antitrust laws if a company dominates the market for a product that customers need, and then forces them to buy a complementary product or service,” Bloomberg writes.

That said, the FTC’s case against Google hinges on whether Android really dominates the market or if consumers have adequate choice. With iOS an extremely popular operating system in its own right, this new antitrust investigation might not have any legs.