The Financial Services Compensation Scheme (FSCS) has begun reimbursing firms some or all of their share of a £326m interim levy after they successfully applied for a refund.
The levy was issued in January to raise money to pay compensation to customers affected by the collapse of investment firms, including Keydata.
Some £100m was levied on investment intermediariers, with £233m levied on fund managers as part of the FSCS's cross-subsidy arrangements.
But the resubmission of tariff data by some investment management and investment intermediary firms has led to refunds.
Requests from other firms who resubmitted their tariff data are still under review but should be resolved by the end of the year, the FSCS said.
"We are pleased to have begun the refund process and will try to complete this as quickly as possible, said Mark Neale, FSCS chief executive.
"We appreciate some firms have not yet had a decision, but we must deal with requests by a process which is fair, consistent and in accordance with the FEES rules."
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