I had a first class seat on a flight last night. The lady in the seat next to mine asked if I would trade with her husband so they could sit together. The husband was two rows up, also a window seat. Trade first class window for first class window? No problem, I took his seat. A minute later, one of the flight attendants asked if I traded seats. I explained the situation and pointed out my original seat. The attendant then goes to the couple and boots them back to coach. I couldn't hear the entire conversation but it sounded like a no trading policy in first class. Is that really a thing or was something else going on?