WASHINGTON (Reuters) -California and three other states on Friday joined the U.S. Justice Department lawsuit aimed at preventing JetBlue Airways (NASDAQ:JBLU) from buying rival discount carrier Spirit Airlines (NYSE:SAVE) for $3.8 billion.
In addition to California, Maryland, New Jersey, and North Carolina signed on to the lawsuit filed in early March.
"We look forward to litigating this important case alongside our state law enforcement partners to stop JetBlue from eliminating its rival, Spirit," Principal Deputy Assistant Attorney General Doha Mekki said in a statement.
The U.S. Justice Department sued on March 7, seeking to stop the transaction, saying the planned merger "will lead to higher fares and fewer seats, harming millions of consumers on hundreds of routes."
Both airlines declined immediate comment on the new states joining.
JetBlue CEO Robin Hayes defended the deal in a Reuters interview this month, saying it would save consumers money and boost available seats.
Adding state attorneys general to the lawsuit could mean extra staffing for litigation, and additional expertise regarding potential effects of the deal on particular states.
The lawsuit is the latest attempt by the administration of President Joe Biden to push back against further consolidation in industries dominated by a few powerful companies.
Separately, Florida Attorney General Ashley Moody had resolved a state probe into the deal after the airlines agreed to increase seat capacity by at least 50% in both Fort Lauderdale and Orlando airports if the merger is completed.