As Lufthansa's 16 euro fee for booking through global distribution channels apparently takes effect, some will seek a "loophole" by using partner codes. However, doing so can cause problems that call into question what the airline industry calls metal neutrality.
Code shares within an airline joint venture provide many more travel options than a single carrier can with its own airplanes. Loyalty program point accrual is (usually) reciprocal. Contracting with multiple partners . . .