The Private Intermittent Securities and Capital Exchange System (PISCES) is a groundbreaking regulatory framework introduced by the UK government to facilitate intermittent trading in private company shares. Launched as a five-year regulatory sandbox in May 2025, it represents a significant innovation in capital markets, creating a regulated middle ground between traditional private ownership and full public listing.
The system was developed to address the growing liquidity needs in the vast private company sector, both in the UK and internationally. According to data from HarbourVest, in the UK there are 2.1 million actively trading companies and more than 215,000 with private equity or venture capital backing. PISCES aims to unlock investment opportunities while supporting the UK’s competitiveness as a global financial centre by providing flexible solutions for companies at different growth stages.
How does the Private Securities Market operate under PISCES?
The London Stock Exchange (LSE) became the first approved PISCES operator in August 2025, launching its Private Securities Market. Unlike continuous public market trading, PISCES operates through periodic auctions that are infrequent and time limited. Companies retain significant control over these events, deciding when their shares may be traded, who can participate, and setting price parameters including floors and ceilings.
The system uses the same auction technology that opens and closes the LSE’s public markets daily, tailored for private market needs. Auctions run from 07:50 to 15:00, with a single uncrossing price that maximises executable trading volumes within company-set parameters. Settlement occurs within two days through CREST, with shares exempt from stamp duty.
Who can participate and what types of auction are available?
PISCES is designed for sophisticated participants only. Eligible buyers include institutional investors, high-net-worth individuals and self-certified sophisticated investors. All existing shareholders, including company employees, can sell shares during trading events, subject to any existing contractual restrictions.
Companies can choose between two auction types: open auctions provide the broadest distribution to all eligible investors globally, maximising liquidity and pricing efficiency. Permissioned auctions allow companies additional control over participation, enabling them to set criteria for who can access information and place orders. This is useful for managing sensitive securities or consolidating ownership structures.
What makes the Private Securities Market different from traditional markets?
The key distinction is the level of control that companies retain while accessing public market infrastructure efficiency. Companies must provide core disclosures set by the Financial Conduct Authority (FCA), but these are proportionate to the intermittent nature of trading rather than continuous public market obligations. Market updates are not required between auctions and UK Market Abuse Regulation does not apply.
PISCES operates a ‘buyer beware’ approach, where investors seek redress directly from companies, in a similar way to private markets. The FCA has created a bespoke statutory liability regime specifically for PISCES, reflecting its unique position between private and public markets.
What are the practical requirements and costs?
Companies must meet two of three criteria: £10m capital raised in the past three years, gross assets over £20m or turnover exceeding £10m. However, the LSE has flexibility to consider other factors for companies not meeting these thresholds.
The fee structure includes introductory rates with no annual fees for 2025–26, rising to £25,000 for 2027–28 and £35,000 for 2029–30. Trading transaction fees start at 0% for both buyers and sellers until June 2026, then 1% for sellers (0% for buyers) until June 2027 and, finally, 0.75% for buyers and 1% for sellers thereafter.
