(Reuters) – Shareholders of U.S. carrier Spirit Airlines Inc voted in favor of JetBlue Airways Corp’s $3.8 billion takeover offer, but face an uphill struggle getting regulators to approve their combination.

Below are the key events of the takeover saga:

Date Development

Feb. 7 Frontier makes a cash-and-stock offer of $25.83/share for Spirit

Airlines

Feb. 8 Lawyers from the U.S. Justice Department say Spirit and Frontier’s

merger to create the fifth-largest airline in the country would

face close scrutiny

March 10 Several public advocacy groups call on U.S. regulators to block

Frontier’s bid for Spirit

April 5 JetBlue makes an unsolicited $3.6 billion, or $33/share, all-cash

bid for Spirit

April 6 JetBlue mounts a vigorous defense of its unsolicited $3.6 billion

bid for Spirit, adding that it is “highly confident” of securing

regulatory approval

April 7 Spirit says that it would enter into discussions with JetBlue on

its $3.6-billion offer as it could likely lead to a “superior

proposal” to the one from Frontier

May 2 Spirit rejects JetBlue’s $33/share offer, saying it had a low

likelihood of winning regulatory approval

May 10 Head of Sun Country Airlines throws his backing behind potential

merger in the ultra-low-cost airline sector

May 11 Spirit says it will hold a shareholder meeting on June 10 for a

vote on its proposed merger with Frontier

May 16 JetBlue makes hostile all-cash takeover offer of $30/share and adds

it was ready to “negotiate in good faith a consensual transaction

at $33″

May 19 Spirit Airlines urges shareholders to reject the hostile offer from

JetBlue, saying it was “a cynical attempt to disrupt” its merger

with Frontier

May 31 Proxy advisory firm ISS urges Spirit shareholders to vote against a

proposed merger with Frontier

June 2 Frontier agrees to pay a break-up fee of $250 million in a bid to

salvage its $2.9 billion acquisition of Spirit Airlines

June 3 Shareholder advisory firm Glass Lewis recommends Spirit Airlines

investors approve Frontier Group’s $2.9 billion takeover bid,

saying it was the “best available” at this time.

June 6 JetBlue sweetens its takeover bid for Spirit by offering $31.50 per

share in cash, comprising $30 per share at deal close and the

prepayment of $1.50 per share of the reverse break-up fee.

June 8 Spirit Airlines delays to June 30 a shareholder meeting to vote on

its proposed merger with Frontier.

June 14 Spirit Airlines said it was in talks with JetBlue Airways and has

granted JetBlue access to the due diligence information being

shared with Frontier Group. Spirit said it was expecting to decide

on the proposal by the end of this month.

June 20 JetBlue Airways said it had sweetened its takeover offer for Spirit

Airlines to $33.50 per share.

June 24 Frontier bumps up the cash component of the deal by $2 per share to

$4.13 per share, prompting Spirit Airlines to urge its shareholders

back a deal with its ultra-low-cost rival at a meeting next week.

June 25 ISS urges Spirit shareholders to vote for a proposed merger with

Frontier after the carrier sweetened its offer.

June 27 Frontier’s Chief Executive Barry Biffle says the revised offer for

Spirit will be enough to secure a merger deal with the

ultra-low-cost carrier.

June 27 JetBlue ratcheted up its bidding war. Offers a “ticking fee”, which

would give Spirit shareholders a monthly prepayment of 10 cents per

share between January 2023 and the closing of the deal, raising the

overall deal value to $34.15 per share.

June 28 ISS says JetBlue’s latest offer is “more favorable” but maintains

its support for the Frontier deal.

June 28 Spirit rejects JetBlue’s sweetened takeover offer and recommends

that shareholders vote in favor of a merger with Frontier at a

meeting on Thursday.

July 7 Spirit postponed a shareholder vote scheduled for July 8 on its

$2.4 billion sale to Frontier so its board can continue discussions

with both Frontier and JetBlue. Spirit said it now plans to hold a

special meeting on July 15.

July 11 Frontier has asked Spirit to delay the shareholder vote on its

proposed offer until July 27, citing the need for more time to

gather sufficient proxy support.

July 13 Spirit said it intends to delay the shareholder vote on its merger

deal with Frontier Group to July 27 as Frontier seeks more time to

drum up proxy support for its buyout bid.

July 15 ISS recommends shareholders of Spirit Airlines to vote against the

proposed deal with Frontier.

July 27 Spirit Airlines said it would go ahead with a vote on its sale to

Frontier, with its shareholders expected to shoot it down,

according to people familiar with the matter.

July 28 JetBlue prevailed in a months’ long bidding war for Spirit Airlines

after the ultra-low-cost carrier accepted its $3.8 billion buyout

deal.

Oct. 19 Shareholders of Spirit Airlines voted in favor of JetBlue’s

takeover offer, moving the companies closer to creating the

nation’s fifth-largest carrier.

(Reporting by Nathan Gomes and Kannaki Deka in Bengaluru; Editing by Shounak Dasgupta, Anil D’Silva and Sriraj Kalluvila)