The tax-avoidance ploy involves shares being donated to charities while their prices are high, allowing the donors to claim a rebate from HM Revenue & Customs of up to 40 per cent on the inflated value (Third Sector, 1 November 2006). When the share price slumps, the shares are worth relatively little to the charities themselves.
Vantis, currently under investigation by HMRC, is alleged to have collaborated with the celebrities and the companies in which the shares were bought.
A spokesman for Vantis said: "Four senior executives within the Vantis tax department are co-operating with HMRC and its enquiries. To date they have not been interviewed and any wrongdoing is strenuously denied."
A leading tax expert told Third Sector he estimated that £100m in tax rebates had been claimed from HMRC by individuals as a result of this ploy.
"This may even be an underestimate," he added. "Many of the accountancy companies involved in this are smaller firms that are difficult to track down."