Three members of the US Congress have written to Spotify CEO Daniel Ek, criticising the streaming platform’s policy for a perceived lack of financial transparency.

An exclusive report by Variety reveals that congress representatives Yvette D. Clarke (New York), Judy Chu (California) and Tony Cardenas (California) penned an open letter dated back to March 26. The letter’s authenticity was confirmed by a spokesperson for Representative Clarke.

The letter states: “If two competing artists both enroll their newest track in the program, any benefit could be cancelled out, meaning that the only profit goes to your company’s bottom line. “For artists of diverse backgrounds, who often struggle to access capital, the premise that they must now pay in order to be found by new consumers on Spotify represents an especially serious problem. “We would ask that Spotify publish, on a monthly basis, the name of every track enrolled in the program and the royalty discount agreed upon,” the letter continues. “Without this transparency, you are asking artists to make a blind choice, and it represents a classic prisoner’s dilemma.”

To read the full letter, check out Variety‘s exclusive report here.