Originally Posted by
rjn21
I'm not an aviation lawyer, but if it comes down to a legal fight (one would hope not - it would appear far easier to claim from any applicable insurer and let them deal with both airlines through subrogation), the Montreal Convention articles 36(3) for multi carrier through tickets and articles 39 to 48 for codeshares seem to suggest that either, or both, the contracting and actual carriers can both be joint and several defendants in any action by a passenger. YMMV.
http://www.jus.uio.no/lm/air.carriag...montreal.1999/
In terms of luggage issues, the responsibility is well established across the industry: all claims have to be put to the last delivering carrier. Not the first or intermediary carrier, nor the one the ticket was bought from or which code is on the ticket, just the airline that was literally supposed to put the luggage on the belt. There is really no scope for doubt and the OP will simply waste time and effort if he tries going through any other airline than IB.
Also, there is really no reason why this should come down to a legal fight. Luggage issues are bread and butter in the commercial aviation world and they are resolved satisfactorily in 99.99% of cases (in fact probably more than that!) without any need to go to court. As others have mentioned, it is best to claim through your travel insurance to start with and they will compensate immediately and deal with the airline afterwards.