Originally Posted by
KLouis
Only thing to be added to what the posters before me wrote is that you should have already OLCId for your LH flight when getting to the check-in counter at SFO, so that you can show them your boarding pass.
I would like to add to this: Its not required that you have done OLCI. If you show your LH ticket/e-ticket itinerary at check-in with UA you should be fine. Regardless of this make sure that you show the UA luggage stubs from SFO at the LH tranfer desk at LHR when you collect your BP for LHR-FRA or to the gate agents (if you do OLCI) in order for them to enter/add your luggage to the LH PNR. Otherwise, most likely your bags will not be loaded on the LH flight because according to the LH system you have no checked luggage.