Originally Posted by
sbm12
They can certainly regulate the means by which you purchase and fly tickets from them but the airlines cannot tell you that you cannot buy a ticket on a different carrier.
If the purpose of buying a ticket on carrier B is to circumvent the fare rules for a ticket from carrier A, why can't carrier A hold that as a violation of their CoC? From my example, I saw nothing in NW's CoC restricting the applicability of the back-to-back ticketing rule to NW tickets.