Originally Posted by 320ToBearz

A short history. Mergers of seniority lists has ALWAYS been a contentious part of ALPA and other unions history in aviation. From the various sell offs of Pan Am to United and Delta and the controversies they caused to the more recent AA/TWA merger. About 65% of all TWA pilots and 100% of their FA's got stapled to the bottom of the AA list. The FA's lobbying in congress got the rules changed to a mandatory process to be followed (Allegheny-Mohawk), which is named after another contentious merger. These basically require a "fair" integration, but such poor wording usually means the two parties cannot agree and it thus goes to a binding arbitration. US Airways pilots thought binding isn't really true and thus quit ALPA in recent years to fight for what they feel should be a "fairer" integration.

Bottom line, is an arbitrator usually makes the decision.