Keystone Law is set to become the third UK firm to list on the London Stock Exchange (LSE), following Gordon Dadds and Gateley.

The mid-market challenger firm plans to join the Alternative Investment Market (AIM) where the new trading entity will be known as Keystone Law Group plc. Corporate broker Panmure Gordon has been instructed by the firm to act as financial adviser during the process.

Shares will begin trading on 27 November and are expected to raise £15m in total, with the placing price of 160 pence per share which values the firm at £50m.

Keystone CEO James Knight said: “I am delighted to announce that we will be joining the AIM market. The entire team has worked hard to establish our position as one of the leading UK mid-market challenger law firms. Our decision to list on the London Stock Exchange will provide us with the most resilient and stable platform to support our ambitious growth plans long into the future.”

Keystone Law was one of the top revenue risers in this year’s UK 200, growing by 22 per cent to £26m during the 2017. The firm also showed one of the highest rises in revenue per partner, up 22 per cent to £4,267 despite a boost in fee-earner numbers.

The firm converted to an Alternative Business Structure (ABS) in October 2013 and received a £3.15m cash injection by private equity firm Root Capital the following year.

London’s Gordon Dadds became the UK’s newest listed law firm earlier this year following a share offer by Work Group and aimed to raise up to £20m via a placing, with the proceeds used to repay borrowings (which then stood at £3.5m), fund acquisitions and provide working capital.

Earlier this year listed firm Gateley posted a 15 per cent rise in revenue to £77m in its second year as a listed entity.