Originally Posted by
Keter
If you ask about codesharing (less likely) then it is only the airlines being parts of the agreement which have the information. For a passenger such information can only be useful for 'free-sell' codeshare agreements when you want to guess whether or not specific class opened by operating carrier will trigger the opening of a certain class by a marketing carrier.
It is also quite useful information on codeshares for *A carriers when trying to determine how many miles one will earn on a trip.