Maybe? All I can say is that last couple of times I transited through LAX, I had to go all the way out through security and passport control - I could have walked out the front doors of the airport - and then all the way back through. It was the same flight number, and the same physical plane that I was getting back on!

I then decided that was too much of a pain, and flew through Dubai instead, which has a vastly superior transit experience!