Tax analysis: This case concerns a challenge to HMRC's implementation of the Foreign Account Tax Compliance Act (‘FATCA’) which requires US nationals living abroad to send personal and financial data to the IRS on a regular basis. If ultimately successful, the claim could have far-reaching implications for the global automatic exchange of tax data between tax authorities further to the Common Reporting Standard. Ms Webster was seeking a declaration that HMRC’s reporting of her UK bank accounts to the US was unlawful. Somewhat curiously Ms Webster’s litigation was funded by an anonymous third party (anonymous even to Ms Webster known only by her lawyers) which prompted much debate. The decision looks in detail at the question of whether a Claimant can refuse to reveal the identity of those funding a claim against HMRC. In rejecting Ms Webster’s application to either strike out HMRC’s defence or grant summary judgment, the High Court found that (1) HMRC’s argument (that Ms Webster’s claim was an abuse of process) had sufficient substance, reality and prospect, and (2) the funder’s identity went to the core issue of whether Ms Webster’s case was a genuine private law claim or an unregulated attack on a government department exercising statutory public functions in the public interest and therefore an abuse of process. The decision provides guidance on both the tests for applications to strike out and for summary judgment applications as well as an insight into the correct way of asserting your data protection rights against public entities. Written by Helen McGhee, partner, and Megan Durnford, associate, at Joseph Hage Aaronson LLP.