Exxon Mobil Corp. filed a notice of appeal to the U.S. Court of Appeals for the Second Circuit Friday, challenging the dismissal last month of its suit against the attorneys general of New York and Massachusetts over allegations their action over whether the energy giant committed fraud by withholding its research on climate change was solely motivated by politics.

U.S. District Judge Valerie Caproni dismissed the suit on March 29, stating from the outset that Exxon was “[r]unning roughshod over the adage that the best defense is a good offense” in its suit against the attorneys general.