The Netherlands international goalkeeper joined Spurs in July but his former club insist that the Swans were obligated to pay them 30 per cent of his transfer fee
The Netherlands international agreed a four-year contract at White Hart Lane in July to bring to an end his three-year spell at the Liberty Stadium.
Vorm started his professional career at Utrecht, making 157 appearances before switching to Wales in 2011 and the Eredivisie side say that, as part of that deal, a 30 per cent sell-on clause was agreed but they are yet to receive any information from Swansea relating to this following the move.
Utrecht general manager Wilco van Schaik slammed Huw Jenkins after the Swansea chairman had reportedly told him Vorm was released on a free transfer, telling BBC Wales : "That's unbelievable and unacceptable.
"Michel is a very reliable goalkeeper in the Premier League. He is 30 years old, in the prime of his life. He still had a two-year contract and has a good reputation.
"Besides that he's a solid member of the Dutch squad. We want to have the 30% as we agreed."
Swansea hit back at the claims, saying that the transfer was "conducted and concluded correctly".