Hello, and sorry to dig up such an old thread.

I recently gained membership of Global Entry and Pre Check, and was able to use Pre Check for the first time a couple of weeks ago departing IAH. Everything worked as expected as far as entering the KTN and at security screening. I was a bit surprised to see “TSA PRE” on the boarding passes (paper and mobile) for my LHR-IAH flight yesterday, though. Does anyone know what purpose, if any, this serves on international flights to the US?