Yes, the OS business class seat is flat, but angled downwards, like the LH seat. I found the LH seat more comfortable, but that could have to do with the fact that it was 3AM when we left and I would have slept on top of a stack of cinderblocks at that point. I found that I slipped down less on the LH seat than I did on the OS seat and that it was more comfortable to sleep on my side & stomach on LH than on OS.