The Spirit Airlines Acquisition Has Taken an Unexpectedly Hostile Turn JetBlue is appealing directly to shareholders.

Back in February, Frontier Airlines announced that it was buying fellow ultra-low-cost carrier Spirit Airlines in a $2.9 billion cash-and-stock deal. But Frontier's hopes for a straightforward acquisition were dashed a couple of months later, when JetBlue made an unsoliticed $3.6 billion all-cash offer to acquire Spirit if it backed out of the merger with Frontier.

But Spirit is holding out for the Frontier deal.

Now, JetBlue is going directly to Spirit's shareholders, CNN reports, trying to convince them to vote against the Frontier deal as it presents an all-cash offer of $30 per share. JetBlue said in a statement on Monday that it was offering a "60% premium to the value of the Frontier transaction," adding that it's willing to negotiate if Spirit discloses more information about its business.

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Frontier's January offer valued each Spirit share at $25.83.

Spirit is citing antimonopoly regulation as a major barrier in the finalization of a deal with JetBlue. Spirit rejected JetBlue's $33-a-share cash offer on May 2, saying that in light of the "substantial completion risk, we believe JetBlue's economic offer is illusory."

If the Frontier-Spirit merger came to pass, the new carrier would surpass JetBlue in size and customer base — becoming the country's fifth-largest carrier.

JetBlue Airways Corporation is down nearly 24% month over month while Frontier Communications Parent Inc has dipped nearly 20% during that same period.

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