London Stock Exchange Group: happy birthday AIM!
AIM is a uniquely British success story – one that has powered scale, created opportunity, and delivered long-term economic value. As we look ahead, it must also be a central part of the UK’s ambition to become a place where companies can fulfil their growth ambitions, says Marcus Stuttard
30 years ago today, the London Stock Exchange launched a new market, AIM, with a bold ambition: to give innovative, high-growth companies the platform they needed to scale, thrive, and succeed. It has more than delivered on that promise.
Since its inception, AIM has supported over 4,000 companies to raise more than £136bn in capital. Many of these businesses have matured into global success stories, employing thousands of people and contributing billions to the UK economy. As AIM turns 30, it remains a vital part of the UK’s capital markets ecosystem – and one of the most successful growth markets in the world.
Yet this anniversary is not just a moment to celebrate, it’s also an opportunity to reflect on the impact of AIM over the past three decades and to look forward to how AIM can continue to evolve. The UK’s capital markets are undergoing significant reform, and there is a clear need to revitalise equity investment and support the next generation of homegrown and global champions. AIM is perfectly placed to play a central role in this future.
Driving growth and economic resilience
AIM’s economic impact is both deep and wide-ranging. In research commissioned by the London Stock Exchange, Grant Thornton found that in 2023, through direct, supply chain and induced impact, AIM companies contributed £68bn to UK GDP and supported over 778,000 jobs. In addition, AIM companies contributed £5.4bn in corporation tax to the Exchequer. From biotech firms advancing cancer treatment to cleantech companies driving the energy transition, AIM businesses are at the cutting edge of innovation and resilience.
Over half of all UK companies on AIM are based outside of London, bringing opportunity and economic vitality to all corners of the UK. And outside of the UK, AIM has welcomed companies from across 68 countries. AIM offers a crucial funding route that aligns long-term capital with entrepreneurial ambition. Almost two thirds of capital raised by AIM companies has been raised post IPO, showcasing its ability to support companies throughout their growth journey. AIM has always been a market with substance over short-term sentiment – a place where founders can retain control and investors can back growth stories from an early stage.
Shaping AIM’s future
This position, however, is not one we take for granted. AIM, like all markets globally, have suffered significant headwinds over the last few years. Smaller companies have been disproportionately impacted by these challenging market conditions.
Against this backdrop, the London Stock Exchange published a discussion paper in April 2025, ‘Shaping the Future of AIM’ which sets out key areas of focus – from enhancing capital inflows to easing areas of friction, whilst maintaining those aspects that remain important for investor confidence. We invited views from across the ecosystem about the areas of the AIM model that they value the most and areas of the framework and market practice that would benefit from reform.
Because while much has changed since 1995, the core principle remains the same: growth companies deserve a market that evolves with them. The need, and scale of the opportunity, to provide an ecosystem that enables young, dynamic, innovative companies to start, grow scale, and stay in the UK is greater now than ever.
Regulatory reform and the role of pensions
AIM is not just a growth market – it is a complementary one. It serves a different cohort of companies than the Main Market, often with different capital needs. But both are essential parts of a healthy funding continuum that seamlessly connects private and public companies, supporting scaling businesses and driving growth. Both AIM and the London Stock Exchange’s soon to be launched Private Securities Market are crucial in achieving this.
The multifaceted reform agenda currently underway in the UK intends to build on the existing strengths of the UK’s capital markets, including measures to unlock greater flows of capital into growth companies, particularly from the country’s pension funds with the recent Mansion House Accord, which includes AIM companies, an important example of this.
However, while initiatives such as the Accord and the existing tax reliefs provide a well calibrated package of support for AIM companies, further action is needed to ensure the recent outflows of capital are reversed, and certainty about the long-term availability of the existing incentives restored.
Conclusion
AIM is a uniquely British success story – one that has powered scale, created opportunity, and delivered long-term economic value. As we look ahead, it must also be a central part of the UK’s ambition to become a place where companies can fulfil their growth ambitions.
Now is the moment to build on 30 years of achievement and chart a course for an even more dynamic, inclusive and growth-focused market that supports the companies of the future.
Marcus Stuttard is head of AIM & UK primary markets at London Stock Exchange Group