Redefining AIM: proposed reforms for 2026 and their impact for prospective issuers

On 4 June 2026, the London Stock Exchange (LSE) published AIM Notice 62, proposing significant reforms to the AIM Rules for Companies and regulatory framework. These proposals build on the LSE’s consultation on ‘Shaping the Future of AIM‘ and its subsequent November 2025 feedback statement.

The proposals reflect a deliberate policy shift towards reinforcing AIM’s identity as a flexible, proportionate, and internationally competitive growth market, and seek to maintain a level of differentiation between AIM and the Main Market following changes to the Listing Rules (UKLRs) introduced in 2024.

The LSE has published its proposed changes to the AIM Rules for Companies alongside AIM Notice 62, seeking feedback from market participants during a final consultation period which closes shortly, on 2 July 2026. Final rule changes will be published thereafter and are expected to take effect later in the year.

This article highlights the key proposed rule changes and their practical implications for companies considering admission to AIM.

A more streamlined and proportionate admission process

A central focus of the reforms is to simplify and modernise the admission process, responding to concerns that AIM admission documents have become overly complex and burdensome to produce relative to their value for investors.

First, the LSE proposes to remove the requirement for a formal working capital statement in the AIM admission document, acknowledging that the cost and evidential burden associated with producing a ‘clean’ working capital statement is often disproportionate to the benefits, given its short-term and binary nature.

Instead, issuers will be required to provide more granular and forward-looking disclosures, addressing their available capital resources, material financial commitments, use of placing proceeds (if applicable), and anticipated future 12-month fundraising needs.

Additional proposals to reduce IPO preparation time and cost include:

• Incorporation by reference, allowing publicly available information to be included in the AIM admission document by reference, via a working hyperlink.
• Greater accounting flexibility – AIM companies incorporated in the UK and EEA will have the option to prepare accounts to their local GAAP, instead of IFRS, meaning in the case of UK issuers to UK GAAP (FRS 102).

Enabling more efficient fundraisings

The LSE proposes to introduce a ‘Capital Access Window‘, where AIM companies undertaking an equity fundraise can voluntarily request a temporary suspension from trading whilst they line up investors. This is intended to give AIM companies greater control over the fundraising process and broaden investor participation, including retail investors. While no fixed timeframe would apply to a capital access window, it is expected to be short, with the LSE assessing requests on a case-by-case basis.

Supporting AIM company acquisitions

The proposals for the treatment of transactions are among the most commercially significant, including:

• Tightened scope for reverse takeovers (RTOs) – currently, transactions exceeding 100% in any of the ‘class tests’ are automatically deemed RTOs, triggering suspension and the requirement to produce a further admission document. Under the new rules, such a transaction would only qualify as an RTO if it also results in a fundamental change in business, board composition, or voting control of the AIM company.

Otherwise, the acquisition would be classified as a substantial transaction, with a disclosure requirement only. The ‘class test’ threshold for a substantial transaction will also be increased, from 10% to 25%, aligning it with the UKLR classification of ‘significant transactions’ for Main Market companies.

• No automatic suspension – guidance would formalise the ability for nominated advisers (‘Nomads’) to request that trading in an AIM company’s shares is not suspended when a proposed RTO is announced prior to publication of an admission document, provided that adequate alternative disclosure is made to the market.
• No supplementary AIM admission document required where there is delay between shareholder approval of an RTO and its completion – provided there is no significant new factor, material mistake or inaccuracy in the information disclosed. The AIM company would be required to notify only key developments and updates post shareholder approval instead.
• Revised approach to option agreements – entry into an option agreement would not be considered an RTO in contemplation where the AIM company has sole control over exercise of the option, the option is unlikely to be exercised or, if exercised, it is unlikely to result in a fundamental change to the company’s business, board, or voting control.
• Changes to ‘class tests’ – the new schedule 3 to the AIM Rules removes the profits ‘class test’ (except in relation to related party transactions under AIM rule 13) and allows a pro rata gross capital class test for investing companies where the acquisition is in line with the investing policy and does not result in control or consolidation.

The proposals signal a more nuanced and pragmatic approach, particularly for acquisitive growth companies.

Enhancing AIM’s appeal to founder-led and high-growth businesses

A key policy objective underpinning the reforms is to make AIM more attractive to founder-led and innovative companies. The new rule changes include:

• Greater flexibility on director remuneration – Nomads would not be required to provide a ‘fair and reasonable’ opinion on non-standard remuneration arrangements where adequate commercial protections (such as good/bad leaver provisions or clawbacks) are in place. All other AIM rule 13 requirements will still apply.
• Special voting share structures – AIM would formally permit shares with enhanced or weighted voting rights, subject to appropriate safeguards in a company’s constitution.

These changes seek to align AIM more closely with global listing trends and address common concerns among founders about loss of control and restrictive remuneration frameworks post-IPO.

Reduced ongoing compliance burdens and a principles-based approach

The new rules also signal a shift towards a more principles-based governance framework.

Specifically, the formal requirement to ‘comply or explain‘ against a named corporate governance code is to be removed; instead, companies will be required to provide tailored disclosure on their governance arrangements in certain key areas, such as board composition, director remuneration and the company’s risk framework.

Additional flexibility is proposed in relation to proxy adviser engagement and third-party commentary. Broadly, AIM rule 26 will be amended to:

• allow voluntary disclosure of proxy advisor engagement via announcement or on the company’s website; and
• enable companies to respond to unauthorised third-party commentary via a notification or their website.

Strengthening AIM’s international proposition

The LSE is seeking to enhance AIM’s appeal as a global growth market through new admission routes.

• A proposed ‘Express Market‘ route would replace the existing AIM Designated Market Route, opening up the fast-track admission process (ie, using a Schedule One announcement rather than a full AIM admission document) to a much broader pool of international listed companies. A minimum market capitalisation of £20 million on admission to AIM would apply. For eligible companies, the Schedule One announcement period would be shortened to three clear business days, and AIM rule 7 lock-in requirements would not apply.
• A new dual listing route would enable simultaneous admission to both an Express Market and AIM, allowing reliance on Express Market admission documentation and limited additional AIM requirements.

These measures are intended to broaden AIM’s international issuer base and position it as an attractive venue for secondary and dual listings.

Greater reliance on Nomad expertise

The LSE proposes removing the current AIM rule 11 disclosure obligations to avoid overlap with UK MAR; instead an amended AIM rule 11 requires companies to maintain adequate systems and controls to identify material changes to their business or prospects. Issuers will be expected to engage proactively with their Nomad, seeking guidance on timely disclosure and its views on market impact.

Alongside these proposals, the LSE has also published a consultation on changes to the AIM Rules for Nominated Advisers and a new technical note setting out expectations regarding Nomad responsibilities.

Altogether, the reforms reflect a continued shift towards a Nomad-led, judgment-based regime, highlighting the Nomad’s role as a strategic adviser rather than solely a compliance gatekeeper.

Reinforcing investor awareness: ‘buyer beware’

Finally, the LSE proposes reinforcing AIM’s long‑standing ‘buyer beware’ ethos more explicitly, including enhanced and prominent disclosure in admission documentation highlighting the higher-risk nature of investing in growth companies and the need for informed investor decision-making.

What this means for prospective issuers

For companies considering an AIM listing, the proposed reforms signal a clear intent to try and reduce some of the upfront cost and complexity of an AIM listing, and, once listed, to provide companies with greater flexibility in structuring and executing transactions, and enhanced alignment with the needs of founder-led and high-growth businesses.

The Nomad model remains in place but with the intention to recalibrate the Nomad role back towards that of a strategic corporate finance adviser.

If you have any queries on the proposed AIM reforms, please contact your usual contact at Penningtons Manches Cooper, or one of our listed contacts.

This article was co-written by Sheelpa Maroo, trainee solicitor.