Navigating FSMA s.90 & s.90A Claims:
From Conscious Awareness To Damages

On 28 January 2026, Fideres hosted an evening seminar featuring a panel discussion with barristers Andrew Onslow KC and Alex Barden KC, alongside Professor Mungo Wilson of the Saïd Business School and Dr. Per Axelson, Co-Head of the Fideres Financial and Securities Litigation Team. Dr. Anne-Florence Allard, a senior associate at Fideres, acted as moderator for the discussion.

The panel focused on recent developments in FSMA s.90 and s.90A claims, with speakers examining key issues of reliance, conscious awareness, market efficiency, and the nuances of different loss methodologies. The session explored how these issues are continuing to evolve in the courts, building on themes first discussed at our October 2025 seminar on reliance, investor behaviour, and the role of economic theory.

Reliance Following Barclays And Standard Chartered

The panel opened with a discussion of the current position following Standard Chartered settling prior to a much-anticipated Court of Appeal hearing. By way of background, in Barclays¹ Mr Justice Leech struck out passive investor claimants, holding that they would be unable to establish reliance, as required by Paragraph 3 of FSMA, Schedule 10A. By contrast, in Standard Chartered², Mr Justice Green declined to follow Leech J’s judgment and refused to strike out the passive claimants, expressing doubts about some of the findings in Barclays.

However, the panel noted that the Privy Council’s recent judgment in Credit Suisse³ may have meaningfully shifted the balance in favour of claimants on the issue of reliance, at least in relation to a strike out application of the kind seen in Barclays and Standard Chartered. While not a securities case, Credit Suisse is relevant to claims under FSMA s.90A because there is a view held by some (most notably Leech J), that Parliament intended the common law test for reliance in the tort of deceit to apply to s.90A claims.

The Privy Council’s judgment in Credit Suisse brings to an end a long-festering issue in the tort of deceit, whether a claimant must demonstrate conscious awareness of a representation in order for a claim to succeed. As the panel observed, Lord Leggatt’s judgment makes clear in robust terms that no such requirement exists, seemingly sweeping away the argument that, in a securities case, a claimant must have actually read the precise published misinformation in question.

There will no doubt be further debate about the precise impact of Credit Suisse on passive investors in FSMA s.90A claims. However, in the context of future strike-out applications, the panel suggested that if the High Court follows the reasoning of Green J, it is highly possible that the Court of Appeal, applying Credit Suisse, might refuse permission to appeal, instead leaving issues of reliance in respect of passive investors to be determined only after a full trial.

Balancing Disclosure Obligations In English Litigation With The Risk Of Foreign Prosecution

The panel next considered a disclosure issue that has arisen in a number of securities cases, most recently in the proceedings against Standard Chartered and Glencore. In Standard Chartered, the bank sought to withhold disclosure of certain documents on the basis of its duties of confidentiality to regulators in Singapore and the US. The relevant regulators had refused consent to disclosure of specific categories of documents, and the bank argued that compliance, even pursuant to an order of the English court, would expose it to the risk of criminal proceedings or regulatory sanctions in the relevant foreign jurisdictions⁴.

Neither Glencore nor Standard Chartered defendants were able to persuade the court that disclosure should be withheld⁵. The panel highlighted the evidential difficulty faced by parties seeking to withhold disclosure in establishing a “real” risk of prosecution.

Market Efficiency And Loss Methodologies

Professor Wilson began the second part of the seminar with an overview of the Efficient Market Hypothesis (“EMH”). According to the EMH, asset prices reflect all available information. As such, prices under the EMH are always “fair,” preventing investors from beating the market – a contention that has helped drive the increasing adoption of passively managed index tracker funds. Crucially for securities litigation, the EMH implies that any material misrepresentation is reflected in the price of the affected securities, providing a direct transmission mechanism between any material misleading information and losses suffered by investors who traded the securities.

In the US, perhaps the most developed securities litigation jurisdiction, plaintiffs who can establish that a security trades efficiently therefore benefit from a presumption of reliance under the so called “fraud-on-the-market” doctrine⁶. US courts have developed a structured framework for assessing market efficiency, most notably through the well-known Cammer⁷ and Krogman⁸ factors which together provide a standardised and concrete approach to evaluating whether a given security is trading in an efficient manner.
The panel then turned to loss methodologies, noting that FSMA provides no guidance on how loss should be calculated in claims under FSMA s.90 and s.90A. Two principal approaches, however, were identified.

First, a rescission-based analysis, which proceeds on the basis that the investor would not have purchased the security at all had all the truth be known. On this approach, any loss flowing from ownership of the security is, in principle, recoverable. Second, an inflation-based analysis, which assumes that the investor would still have purchased and sold the security (but at different prices) absent the alleged misstatement or omission.

An inflation-based methodology seeks to estimate the amount of price inflation attributable to the impugned misrepresentation—the difference between the actual market price of a security and the price that would have prevailed had the market known the truth. In US securities litigation, the most widely accepted technique for doing so is an event study, which is a statistical technique to quantify the price impact of public disclosures, accounting for concurrent market and industry developments.

While the relative simplicity of a regression-based event study has contributed to its widespread adoption as the method of choice, the panel noted that this is not the only available approach. Within the event study framework itself, novel approaches such as synthetic controls could potentially be used to estimate the counterfactual price.

The panel briefly addressed the inherent difficulties in estimating an unobservable counterfactual, particularly the challenge posed by confounding information entering the market, which can complicate the identification of the price impact of an individual piece of information.
In closing, the panellists observed that no group litigation claims under s.90 or s.90A have yet proceeded to trial. As a result, there has been very limited guidance from the English courts on the assessment of loss, leaving parties to deploy the available analytical tools and, inevitably, creating significant scope for robust debate between experts and lawyers.