Credit bureau Equifax Inc. is asking the U.S. Supreme Court to hear appeal from an adverse tax ruling in Mississippi.

The appeal is a reaction to a 2013 Mississippi Supreme Court decision that Equifax had to prove that it didn't earn any taxable income in the state. The state Department of Revenue examined Equifax's income and allocated some to Mississippi, ruling it owed taxes and penalties.

The state Department of Revenue has a deadline of May 23 to file a response to Equifax's petition.

The Mississippi court upheld the Revenue Department's applying a market-based tax apportionment method to determine the tax bill of Equifax. The market-based method calculated the company's taxes based on revenue earned in Mississippi, thus increasing its tax liability from zero to over $700,000, according to court documents.

Lawmakers responded during the 2014 session to change how Mississippi state government collects taxes.