[Last updated: 1 February 2026, unless otherwise noted]

The London Stock Exchange (more commonly referred to as the LSE) operates the following markets:

• The Main Market (a UK regulated market) comprising several categories including the Commercial Companies (Equity Shares) category, the International Secondary Listings (Equity Shares) category, the Equity Shares (Transition) category and the Shell Companies (Equity Shares) category, amongst others.
• AIM (formerly known as the Alternative Investment Market) (an exchange regulated market or UK multilateral trading facility (UK MTF)).
• London Stock Exchange Stock Connect (The Shanghai-London Stock Connect & the Shenzhen-London Stock Connect).
• The Specialist Fund Segment (SFS).
• The Sustainable Bond Market (SBM).
• The Professional Securities Market (PSM) (an exchange regulated market or UK MTF) - Note that with effect from 19 January 2026, new admissions of securities to the PSM are not possible. Transitional provisions apply for issuers with existing PSM listed securities so that these securities will remain listed and admitted to trading on the PSM for as long as the LSE chooses to maintain it.
• The International Securities Market (ISM) (an exchange regulated market or UK MTF).

This summary relates only to AIM, a designated small and medium-sized enterprises (SME) Growth Market, which is the LSE's international market for smaller, growing companies from a wide range of countries and sectors. AIM was founded in 1995 and is known for its balanced approach to regulation, which is well-suited to smaller companies. The AIM rules are concise and principles-based. Generally, the business of a non-UK incorporated company seeking a quotation on AIM should be international and not limited to its local market. Certain types of companies, such as natural resources and technology companies, are by their nature international. Other types of companies should at least have international markets or seek to expand internationally.

The principal advantage of an admission to AIM is its balanced regulatory environment, which is designed to meet the needs of smaller and growing companies while offering appropriate investor protection. The entry criteria are tailored to growing companies and, as described in more detail below, there are generally no minimum requirements as to trading record, public float and market capitalization (except for investing companies). In addition, generally, applicants are not required to have a prospectus approved by the UK Financial Conduct Authority (FCA) to conduct their offering, instead they are required to publish an MTF admission prospectus (or Admission Document) which is reviewed by the LSE.

Other advantages for a company joining AIM include: access to a diverse and highly knowledgeable international investor base keen to provide capital to support growing companies; the existence of a large and experienced community of advisers and liquidity providers to help companies join AIM and support them after admission; a market in which companies can use shares as currency, to make acquisitions and grow the business; and the associated visibility and profile raising with customers, suppliers, investors and other stakeholders on an international scale.

The LSE does not make any distinction between primary and secondary listings or quotations in respect of admission to AIM, as AIM companies are admitted to trading on AIM rather than listed. Therefore, by virtue of not being listed, AIM companies are not included in the list of securities that have been admitted to listing (the Official List), which is maintained by the FCA, unlike companies with shares listed on the Main Market of the LSE.

As of 31 December 2025, the aggregate market capitalization of companies admitted to trading on AIM was approximately £64.52 billion (approximately US$86.93 billion). This represents a decrease of approximately 18.3% since December 2023, when aggregate market capitalization was approximately £78.96 billion (approximately US$106.38 billion). AIM is an international market for smaller and growing companies. Admission to trading on AIM is available to companies from all sectors and from all over the world, and a diverse range of such companies have been admitted to trading.

As of 31 December 2025, there were 619 companies (December 2024: 685) admitted to trading on AIM. Of these, 530 (December 2024: 541) were domestic and 89 (December 2024: 144) foreign. However, note that some of the domestic companies are UK holding companies of foreign companies with foreign operations formed for the purpose of facilitating AIM admission.

Application will need to be made to the LSE for any proposed admission to trading on AIM. As AIM is not a regulated market for the purposes of the Public Offers and Admission to Trading Regulations 2024 (POATRs), no prospectus will be required. Companies applying for admission to AIM whose securities are not already quoted on other markets designated by the LSE are required to produce an Admission Document. The Admission Document is reviewed, but not pre-vetted, by the LSE. The FCA is therefore not typically involved in an AIM admission.