Utrecht negotiated a sell-on fee in Vorm's deal when he moved to Swansea in 2011.
For the moment, however, Utrecht general manager Wilco van Schaik is in the dark over how much they're due.
"We hope to get clarity this week," Van Schaik told Voetbal International. "It's a waiting situation for us, you hear and read different amounts. Therefore, we do not count ourselves rich.
"Michel is one of the best goalkeepers in the Premier League and at Swansea he had a commitment for two years. They would certainly have not let him leave lightly."
For the big stories and the banter follow us on Twitter: @tribalfootball