The Financial Services Compensation Scheme (FSCS) could bill investment advisers a further £30m after returning the money to firms who miscalculated their levies.
A number of firms applied to the scheme for a reduction in their levy due to errors in the tariff data submitted by them to the FSA.
In its annual report and accounts the FSCS said it is still investigating the claims, which total nearly £80m, and has set aside a provision pool for refunds of £30m.
The shortfall created by refunding firms which overpaid may lead to further levies for other advisers, the FSCS said.
"A number of firms have applied for a reduction of the amount levied due to errors in the tariff data submitted by them to the FSA....Based on the best information available to the directors, provision for £30,000,000 has been made in the accounts.
"The claims are currently being investigated and any amount eventually repaid is likely to be levied in 2011/12. The final outcome may potentially result in a material adjustment to the provision being required," the report said.
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