Linear Investments v FOS: Elective Professional Clients, COBS 3.5, and the limits of self certification

The Court of Appeal’s decision in Linear Investments Ltd v Financial Ombudsman Service [2025] EWCA Civ 1369 provides clear guidance on the operation of the FCA’s client categorisation rules in the Conduct of Business Sourcebook (COBS) 3.5. The judgment confirms the objective nature of the qualitative and quantitative tests for elective professional client status and explains why untested self‑certification is inadequate where information is inconsistent or incomplete. It also clarifies that contributory negligence can reduce redress where a client’s misstatements are an operative cause of loss.

Background to the dispute

Linear, a specialist investment firm, accepted a retail client into its “Pembroke” managed strategy, a computer‑driven approach that made extensive use of short‑dated, leveraged CFDs and was intended for professional investors. The client completed onboarding documents, sought elective professional status, and later suffered substantial losses. He complained to the FOS. The Ombudsman upheld the complaint, finding that Linear had not properly assessed the client’s knowledge and experience, and awarded full redress calculated against a FTSE UK Private Investors Income total return index, plus interest. 

Subsequently, Linear brought judicial review proceedings. The Administrative Court dismissed the application. On appeal, the Court of Appeal dismissed the appeal on liability and upheld the FTSE benchmark, but allowed Linear’s appeal on contributory negligence, remitting that issue to the Ombudsman for reconsideration.

COBS 3.5: how the rules operate

COBS 3.5 distinguishes between professional clients and elective professional clients. A firm may treat a client as an elective professional client only if all the following requirements are satisfied:

• The qualitative test under COBS 3.5.3R(1): the firm undertakes an adequate assessment of the client’s expertise, experience and knowledge that gives reasonable assurance, in light of the services or transactions envisaged, that the client is capable of making their own investment decisions and understanding the risks involved.
• The quantitative test under COBS 3.5.3R(2): for MiFID business, at least two of the specified criteria are satisfied (e.g., trading frequency “in significant size, on the relevant market”, portfolio size exceeding €500,000, or relevant professional experience). 
• The procedural steps under COBS 3.5. 3R(3): the client’s written request, clear written warnings about loss of protections, and a separate written acknowledgment of the consequences. 

The Court emphasised that these are objective regulatory standards. The issue is not whether the firm has collected signed statements, but whether its overall assessment meets the regulatory threshold of adequacy and reasonable assurance for the particular product and risks, here, leveraged CFD trading in a strategy expressly designed for professional investors. 

Why self‑certification was insufficient

The Ombudsman found, and the Court agreed, that Linear’s acceptance of tick‑box assertions without corroboration did not satisfy the qualitative test. Three features were decisive:

• The firm’s own documentation contemplated more than tick‑boxes. The forms required a brief explanation of the client’s relevant experience and knowledge and called for supporting evidence to justify elective professional categorisation. None was provided. Proceeding regardless meant the firm failed to meet the standard of an “adequate assessment.” 
• A clear inconsistency triggered a duty to inquire. The client ticked boxes for extensive CFD experience, yet his narrative answer referred only to long-term investing in “blue-chip stocks”. Given the fundamental differences between conventional equity investing and leveraged CFD speculation, that that omission called into question whether he understood the product and its risks. Linear should have probed and obtained evidence, did not. 
• Unsupported claims of professional experience required scrutiny. The client indicated a year’s work in the financial sector relevant to the trading envisaged but provides no particulars. In light of his stated 12‑year academic employment, Linear needed to clarify recency, relevance and substance. It did not. 

Taken together, these points mean firms cannot rely on untested self‑certification where the information is inconsistent, incomplete or unsupported. Where a firm’s process requests evidence, failure to collect it undermines the reasonable assurance required by COBS 3.5.3R(1). 

The quantitative test: getting beyond “lots”

The Court also agreed that the quantitative limb was not satisfied. COBS 3.5.3R(2)(a) requires that the client has undertaken transactions “in significant size, on the relevant market” with a specified frequency. Recording average CFD trade size in generic “lots” was not sufficient. Lot sizes and conventions vary by market. Without specifying the underlying markets and the actual lot sizes used in those markets, a firm cannot relate asserted experience to the proposed CFD activity. Linear’s form design did not elicit this market‑specific detail, and no supporting documentation was provided.  On that basis, the quantitative criterion was not met.

The Court of Appeal’s decision

The Court of Appeal dismissed Linear’s challenges on liability and upheld the FTSE benchmark as a rational basis for fair compensation. It allowed the appeal on contributory negligence and remitted that issue for reconsideration. Five points follow: 

1. The qualitative and quantitative tests under COBS 3.5 require an objective, evidence‑based, product‑specific assessment that gives reasonable assurance of competence and risk understanding. Tick‑box assertions are a starting point, not an end point. 
2. Where onboarding information is inconsistent or incomplete, firms are put on inquiry and must obtain clarification and corroborative evidence before categorising the client as professional. 
3. To demonstrate trading “in significant size, on the relevant market”, firms must capture market identifiers and lot conventions. Generic references to “lots” do not satisfy the rule. 
4. The FTSE UK Private Investors Income total return index was a logical benchmark where the firm failed to establish that the client understood or accepted the higher risks of the professional‑only strategy. 
5. A client’s misstatements about CFD experience and financial‑sector employment were an operative cause of loss. Common‑sense causation applies even‑handedly to claimant and defendant fault; where both contribute, apportionment is required. 

Contributory negligence

The Ombudsman’s refusal to make any reduction was based on an inaccurate approach to causation. Even if Linear’s other failings (including unclear or misleading information on risk and cost) were operative causes, the client’s misstatements were also operative causes. But for those misstatements, he would not have been accepted as an elective professional client, would not have accessed the professional‑only strategy, and would not have suffered the losses. The Court therefore remitted the issue so that the Ombudsman can determine a just and equitable reduction reflecting the client’s share of responsibility.

Practical implications

This decision offers clear lessons for firms:

1. Treat the qualitative test as an assessment grounded in narrative and documentary corroboration. If your process asks for explanations and evidence, obtain and review them before classification. 
2. Capture what the quantitative test requires: identify the markets traded and the lot sizes used, not simply “lots”. Seek particulars of any claimed professional experience (role, responsibilities, dates, relevance). 
3. Where assertions conflict with narratives or external facts, follow up. “Reasonable assurance” means clarifying and testing plausibility before granting professional status, particularly for leveraged derivatives. 
4. Assessments are judged against the specific risks of the envisaged strategy. General investment sophistication is not a substitute for demonstrated understanding of CFDs and leverage.
5. Where client misstatements enable access to unsuitable services, expect potential reductions in redress for contributory negligence alongside any firm failings. 

Takeaways

The judgment therefore serves as a reminder that elective professional classification under COBS 3.5 requires a documented, product‑specific assessment that meets both qualitative and quantitative standards, and that client misstatements can, and should, affect the fairness of any compensation outcome. 

Please click here for a copy of the judgment.

This article was co-authored by Shaina Haria, Trainee Solicitor.

For further information on how this case may affect your business, please contact Kushal Gandhi and/or Jonathan Monks.