Samsung is sourcing its flagship sensors from its own division and Sony. It’s not unexpected at all, as the company has been doing this since 2014. The next Galaxy Note model is tipped to feature the same sensors.
When it comes to mobile components, Samsung certainly has its fingers in plenty of pies. But Samsung’s flagships seem to be so popular that the company has to source components from elsewhere too. This is indeed the case with the Galaxy S9 camera sensors.