Only days after Sprint overwhelmingly approved SoftBank’s takeover bid, the third-largest mobile operator in the US must now face a $300 million lawsuit filed by the New York Attorney General alleging deliberate failure to pay sales taxes.

In a public announcement issued 1 July, New York Supreme Court Justice, O. Peter Sherwood, confirmed that an earlier Sprint motion to dismiss the lawsuit had been denied.

“Sprint is disappointed in the Court’s decision, and we intend to file an appeal shortly,” Sprint said in an emailed statement quoted by Reuters.

“With this lawsuit, the Attorney General’s office is claiming New York consumers, who already pay some of the highest wireless taxes in the country, should pay even more.”

Reuters reports that the lawsuit, brought by New York Attorney General Eric Schneiderman, was the first tax enforcement action filed under the state’s False Claims Act.

And under the Act, whistle-blowers can receive up to 25 per cent of any money recovered as a result of their information.

Schneiderman, using whistle-blower information, alleges that Sprint – in an attempt to woo customers away from AT&T and Verizon with cheaper services – failed to bill customers for more than $100 million in taxes for its wireless services over seven years.

The lawsuit seeks three times the amount of underpaid tax, plus penalties.

A spokesman for Schneiderman, quoted by Reuters, said the ruling “sends a message that tax dodgers will be exposed and prosecuted to the fullest extent of the law”.

Lawyers for both sides have been ordered to appear at a hearing 24 July.