spirit airlines inc save said thursday its board has unanimously determined that jetblue airways corps jblu 30ashare cash offer is not in the best interest of the airline and its shareholders and is urging the latter to reject the tender launched by jetblue earlier this week in its comprehensive analysis the board determined that the jetblue transaction faces substantial regulatory hurdles especially while the northeast alliance nea with american airlines aal remains in effect and is as a result not reasonably capable of being consummated and is not superior to spirits agreed merger transaction with frontier ulcc   spirit had already reiterated earlier in may its support for the merger deal with frontier group holdings inc that it had agreed before jetblue swept in with an offer the airline said it does not believe that a deal with jetblue would be approved by the regulator spirit shares were down 17 premarket jetblue was down 03 and frontier was down 36 the us global jets etf jets has fallen 7 in the year to date while the sp 500 spx has fallen 177