CONCORD, N. H. – A federal appeals court in a split decision on Monday rejected the Pan Am pilots’ claim of union-busting and ruled that Guilford Transportation acted legally when it transferred its airline business to nonunion Boston-Maine Airways.

The appeals court in Boston ruled in the dispute between the Air Line Pilots Association and Guilford Transportation, which shut down Pan Am in October and transferred its flights to Boston-Maine.

Also that month, U.S. District Judge Joseph DiClerico in Concord issued an injunction requiring Guilford to “restore to the status quo” the pay, rules and working conditions to uphold the contract between the union and the company until all dispute-resolution options are exhausted.

The union argued that the shutdown and use of Boston-Maine charter services for traditional Pan Am flights violated DiClerico’s order. But later, U.S. Magistrate James Muirhead said Boston-Maine developed its charter business independently.