The EU is taking another look at Apple’s iMessage, as well as Microsoft’s Bing, to see if those services should be regulated by the Digital Markets Act (DMA).

The EU rolled out the DMA in an effort to regulate Big Tech and level the playing field for small rivals. The DMA calls for gatekeeper companies to make their services interoperable with those of rivals.

Apple and Microsoft initially argued — successfully — that their services did not have enough users in the EU to cross the threshold where they would fall under the DMA. According to Reuters, however, the EU Commission is asking Apple and Microsoft’s users and rivals whether their services should fall under the DMA after all.

If Apple’s iMessage is found to be a gatekeeper service, it would force Apple to make iMessage interoperable with services like Signal, WhatsApp, and Google’s RCS messaging.