The Supreme Court unanimously dismissed the appeal brought by BlueCrest Capital Management (UK) LLP (Bluecrest), holding that (i) its members met Condition A (in section 863B of the Income Tax (Trading and Other Income) Act 2005 (ITTOIA 2005)) because most of their remuneration was ‘disguised salary’ and (ii) the First-tier Tax Tribunal (FTT) had applied the wrong legal test in determining whether certain members held ‘significant influence’ (for the purposes of Condition B in ITTOIA 2005, s 863C) over the affairs of Bluecrest. The Court also confirmed that (i) Condition B is concerned with members’ legally enforceable rights and duties under a limited liability partnership (LLP) agreement, rather than informal influence arising from the members’ performance or responsibilities, (ii) responsibility for high-value day-to-day investment decisions does not, of itself, amount to significant influence over the affairs of an LLP and (iii) on the facts of the case, remuneration calculated primarily by reference to individual investment performance, subject to an overall profits cap, constituted ‘disguised salary’ for the purposes of Condition A. As well as summarising the decision, this News Analysis contains commentary from Henry Bennett-Gough, Partner at Simmons & Simmons LLP, and Matt Marfani, Director at ADE Tax, on the implications of the judgment.