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London Stock Exchange
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London Stock Exchange

UK's primary securities exchange, part of London Stock Exchange Group, running the FCA's PISCES market.

London Stock Exchange's Private Securities Market completed its first PISCES trading event in March 2026, part of the FCA's pilot for pre-IPO share liquidity that runs as a regulatory sandbox until 2030.

Last refreshed: 22 September 2026 · Appears in 1 active topic

Key Question

Is the London Stock Exchange losing its grip on UK tech company listings?

Timeline for London Stock Exchange

#8 8 Jun

Mentioned in: Cosine builds Britain's sovereign AI model

UK Startups and Innovation
#8 12 May

Mentioned in: Nine of 14 Reform councils raise council tax

UK Local Elections 2026
#69 15 Apr

Mentioned in: Cooper claims halt; Kpler counts 8

Iran Conflict 2026
#1 18 Mar

Completed first PISCES trading event via its Private Securities Market

UK Startups and Innovation: PISCES runs first pre-IPO trading events
#1 1 Mar

Mentioned in: Nscale raises $2bn in record European round

UK Startups and Innovation
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Background

London Stock Exchange, the UK's main securities exchange, traces its origins to 1801 and now operates as the trading Arm of London Stock Exchange Group (LSEG), which itself lists on the exchange it owns. LSEG's 2021 acquisition of Refinitiv for $27bn shifted the group's revenue mix, so data and analytics now outweigh income from trading fees.

In 2026 the exchange's Private Securities Market completed its own first live PISCES trading event; broker JP Jenkins ran a separate first window from 18 to 24 March the same month. PISCES lets private companies offer shareholders periodic liquidity without the disclosure burden of a full listing, addressing a wait of seven to ten years UK startup employees have historically faced for any exit.

LSEG's reach extends beyond trading. Its Kpler-partnered tanker-tracking data has been cited by observers assessing Hormuz shipping disruption, and the group joined a thirteen-company Coalition, including Lloyds Banking Group and BAE Systems, backing London AI startup Cosine's sovereign model in June 2026.

Common Questions
What is PISCES and why does the London Stock Exchange want it?
PISCES is a new UK regime for pre-IPO trading. The LSE hosted the first session and backs the concept as a way to keep high-growth companies within the UK capital markets ecosystem before they list.Source: uk-startups-and-innovation
Why are UK tech companies listing in New York instead of London?
Companies cite deeper US investor pools, higher valuations, and lighter ongoing disclosure burdens. The LSE and UK Government are attempting reforms including PISCES to address this.Source: uk-startups-and-innovation
Does the London Stock Exchange own Refinitiv?
Yes. LSEG acquired Refinitiv in 2021 for approximately $27bn, making it a major financial data business alongside its exchange operations.Source: uk-startups-and-innovation
What is PISCES and who runs it?
PISCES (Private Intermittent Securities and Capital Exchange System) is an FCA sandbox letting private companies offer share liquidity before an IPO; the London Stock Exchange's Private Securities Market and broker JP Jenkins both ran first trading windows in March 2026.Source: Lowdown
Why did Nscale choose New York over London for its listing?
Nscale filed for a New York Stock Exchange listing on 18 September 2026 at a $14.6bn valuation; the filing did not name the LSE as an alternative venue considered.Source: Lowdown
Who is backing Cosine's Lumen Sovereign AI model?
A thirteen-company Coalition including London Stock Exchange Group, Lloyds Banking Group, NatWest Group, BT and BAE Systems backs Cosine's Lumen Sovereign model, unveiled 8 June 2026.Source: Lowdown

Written with AI from Lowdown's published reporting. Not individually reviewed by an editor. Updated 22 September 2026. Editorial standards.