Freedom SIPP has been wound up by the High Court, leaving its clients facing up to £66m in tax charges.
HMRC applied to have the SIPP provider wound up in August after a dispute over outstanding VAT payments.
Freedom SIPP first ran into trouble in December 2008, when it closed to new business following FSA concerns over its administration processes.
The High Court has now wound up the firm, and HMRC is expected to de-register the pension scheme, meaning clients could face a substantial tax charge.
When the scheme is de-registered, its assets will face an instant 40% tax charge, passed on to clients as part of Freedom's standard terms and conditions.
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