Swansea Supporters Trust vice-chairman Jim White says that he has yet to see any evidence that the group finalising an agreement to purchase a controlling interest has any money to invest in the club.
The club confirmed on Saturday that American duo Steve Kaplan, the co-founder of Oaktree Capital Group and vice chairman of the NBA's Memphis Grizzlies, and D.C. United managing general partner Jason Levien, are in talks.
However the Trust, which currently own a 21 percent stake in the club, insists it has not seen any additional information.
"This is a sale of shares, there's no other way to describe it at the moment," White told BBC Radio Wales. "The reality is we have not seen any details of investment.
"We have not been party -- and are disappointed about that -- to the same level of information as other shareholders have had, but from what we have seen, this is a share sale.
"We know the club needs to move forward, the trust is not against investment, we know the club needs to move on and progress.
"But we have not seen any details or further information around investment as such. No one doubts investment is needed, but look at Leicester City -- they have a similar wage bill to what we at the Swans have. They have shown you can compete without billions of pounds."
A deal reportedly worth around £100 million is expected to be finalised in the coming weeks.