The Supreme Court just told a $100m trader his influence doesn't count
BlueCrest's traders ran nine figure books, took the big decisions daily, and everyone in the building listened when they spoke. On 1 July the Supreme Court said none of that matters, because influence over a firm only counts if the paperwork actually gives it to you. Nearly £200m rested on the answer, and it reaches every partnership in the country.
Picture one of the most important people at a hedge fund. He manages over $100m of the firm's money and decides, every day, how to invest it. He is consulted on hiring. When he talks, people listen. Is he a partner in the business, or is he an employee?
On 1 July the Supreme Court answered that question, and it was not the answer the firm wanted. The case is HMRC v BlueCrest Capital Management [2026] UKSC 18, it is the biggest partnership tax case in years, and the bill behind it is nearly £200m.
The test with three questions
Since 2014 there has been a rule designed to catch people who are partners on paper but employees in reality. It asks three questions about each member of an LLP. Is their pay basically a salary, rather than a genuine share of the firm's profits? Do they lack any real say in how the firm is run? And have they put in only a small amount of their own capital? Answer yes to all three and the taxman treats that person as an employee, which means PAYE and, more painfully for the firm, employer's national insurance at 15%. Escape even one question and they stay a partner.
BlueCrest accepted the capital question was a yes. So everything came down to the other two, and the firm was confident on both. Its traders were paid out of profits, and they were obviously influential. What could be more influential than deciding how $100m gets invested?
Why "obviously influential" wasn't enough
The court took the two arguments in turn, and its answers are easy to state.
On pay, the traders were rewarded on their own results, not the firm's. A bonus based on your own numbers is how employees get paid at every bank in the City, and calling the pot it comes out of "profits" does not change that. A genuine partner shares in what the whole firm makes. These traders did not.
On influence, the court drew a line that will now matter to every partnership in the country. The law asks what rights the members' agreement actually gives you, and not how important you are in practice. Being brilliant at your job does not count. Being trusted, senior, or the person everyone consults does not count. The judgment even says being "an excellent rainmaker" does not count. What counts is what is written down, and on BlueCrest's own paperwork the firm was run by a board that did not include a single one of these traders. They had influence, but nobody had ever given it to them. For this test, that is the difference between a partner and an employee.
The echo of two weeks ago
If this sounds familiar, it should. Two weeks ago I wrote about HFFX, where a firm labelled £22.5m of trader rewards as "capital" and the Supreme Court looked straight through the label and taxed what the money really was. Now the same court has ruled that traders with very real influence had none in law, because no document conferred it.
It looks like the court changed its mind about whether reality or paperwork wins. It did not. In both cases it answered exactly the question the law asks. For the money, the law asks what a payment is really for, so the label lost. For influence, the law asks what the agreement really grants, so the corridor reputation lost. Both times, the court went to the file and believed nothing else.
This is not a hedge fund story
The same three questions apply to every LLP, and that includes accountancy firms, law firms, surveyors, architects and consultancies. The person to think about is the fixed share partner. Paid a mostly fixed amount with a little on top, so question one is a yes. Not on the management board and holding no vote that decides anything, so question two, after this judgment, is a yes on the paperwork alone. Capital contribution modest, so question three is a yes. Three yeses, and years of employer's national insurance arrive at once.
There is one more detail worth knowing. BlueCrest's case now goes back to the tribunal to be decided under the correct test, and the firm is not allowed to file any new evidence. Whatever its documents said on the day, that is the record it must live with. Every other firm still has time to look at its own members' agreement and ask whether it matches reality. If your fixed share partners genuinely help run the firm, the agreement should say so, in committee seats and votes on things that matter.
Five justices and 137 paragraphs, and the lesson fits on a sticky note. Influence you exercise is a fact. Influence you were given is a right. Only the second kind counts, so if it matters, write it down.
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