The Seneca Nation of Indians has decided to stop sharing its casino revenue with the state of New York, effectively picking the scab off an old tribal-state wound that had only just begun to heal.

On Wednesday, the Senecas announced that their three upstate casinos in Buffalo, Niagara Falls and Salamanca would cease providing the state with a 25% share of their slot machine revenue as of April 1. The tribe has anted up nearly $1.5b to the state over the life of its tribal-state compact, which was signed back in 2002.

The Senecas insist that they’re acting within the terms of their compact, which called for an initial term of 14 years, with an option to extend the compact for a further seven years. The compact is now in its 15th year, and the tribe says there’s nothing in the extension language that requires them to continue making the payments.

State officials were reportedly caught off guard by the Senecas’ decision, but the Buffalo News quoted an unidentified Seneca representative saying the tribe’s stance was “nothing new. It’s what the compact says in black and white language.”