Sightings of the mythical unicorn have become more common in the UK. The country has been the birthplace of over 70 startups valued at over £1 billion and trails only the US and China in the global ranking, according to data from Tech Nation and Dealroom.

However, there are growing signs that they might be part of a dying breed. The high-profile debacle of WeWork's IPO and the string of other unicorns that have recently gone public in the US while remaining unprofitable have caused concern among investors that these companies are overvalued and that their founders have excessive voting control over the businesses.

Read next: Five takeaways from the WeWork IPO

The dramatic drop in the valuation of BenevolentAI suggests that these investor fears have spread across the Atlantic. Nonetheless, investment banking firm GP Bullhound predicts that 17 more companies in the UK will join the unicorn blessing by 2021, including challenger bank Starling, payments company GoCardless and lawtech startup Luminance.

We'll be checking if they can progress onto our list of UK unicorns, ranked below in order of most recent valuation.

Read next: What is a tech unicorn? And where did the term come from?

Global Switch


Global Switch reached a whopping £8.4 billion valuation in 2018 after property tycoons the Reuben brothers sold half their stake in the company to a consortium of Asian investors ahead of an anticipated float.

In January 2019, Sky News reported that the data centre operator was planning a stock market listing in Hong Kong that could push its value beyond £9 billion. 

The company was founded in 1998 and has grown to own 11 data centres across Europe and the Asia-Pacific region, earning the world's highest credit rating for a data centre provider on the way.

Valuation: $11 billion (£8.4 billion)

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The Hut Group (THG)


Online beauty retailer The Hut Group rebuffed a series of takeover bids and investment offers in 2018 that valued the company at nearly £4 billion, according to reports in Sky News.

The Hut Group expanded rapidly after it was founded in 2005 by Matthew Moulding and John Gallemore, two former employees of telecoms company the Caudwell Group. Its current brands include Zavvi, Myprotein and Lookfantastic.com.

The Cheshire-based e-commerce group was previously valued at £2.5 billion after selling a £125 million stake in the company to Mutual Global Investors (OMGI) in August 2017.

Valuation: $5.1 billion (£4 billion)

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Greensill


Invoice financing business Greensill became a unicorn in July 2018 after receiving a $250 million (£189 million) investment from General Atlantic, valuing the company at $1.64 billion. In May 2019, its valuation rose to $3.5 billion after SoftBank Vision Fund, the world's largest technology investor, ploughed another $800 million into the company.

Greensill aims to provide working capital finance for companies globally on terms that fit the precise requirements of each client.

The seven-year-old company was founded by Lex Greensill, who was raised on a sugar cane farm in Queensland, Australia and went on to establish a supply chain finance team at Morgan Stanley in London. He was awarded a CBE in 2017.

Valuation: $3.5 billion (£2.75 billion)

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BGL Group


Insurance and financial services company the BGL Group was valued at £2.25 billion after the Canada Pension Plan Investment Board (CPPIB) spent £675 million for a 30 percent stake in the business.

The Compare the Market owner had been preparing for an IPO, but changed its plans after receiving a number of approaches from investors. The proposals were assessed through a competitive process, which selected CPPIB as the best partner for the company.

BGL was founded in 1992 by South African entrepreneur Douw Steyn and now boasts 9.5 million customers across its selection of insurance, price comparison, and financial services products.

Valuation: $2.9 billion (£2.25 billion)

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OakNorth


Digital banking startup OakNorth earned a $2.8 billion valuation in January 2019 after raising $440 million in an investment round led by SoftBank's Vision Fund, the Japanese mega-fund's first major fintech deal in Europe.

OakNorth provides flexible loans to small business owners, and a bespoke debt finance platform called OakNorth Analytical Intelligence. It was founded in 2015 by Rishi Khosla and Joel Perlman, who got the idea from their own struggle to secure capital for their previous business, Copal Amba.

The company first hit the $1 billion valuation benchmark in October 2017, which made it the first digital challenger bank in the UK to reach unicorn status.

Valuation: $2.8 billion (£2.2 billion)

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Monzo


Challenger bank Monzo joined the unicorn club in October 2018 after raising £85 million in a Series E funding round that valued the company at £1 billion. That figure doubled to £2 billion in June 2019, when the mobile-only bank raised £113 million in a new funding round led by renowned US accelerator Y Combinator.

Monzon was founded in 2015 by Tom Blomfield, who launched the company after leaving the challenger's chief rivals, Starling Bank, under mysterious circumstances.

His venture has gone on to earn a UK banking license and more than two million loyal customers.

Valuation: $2.5 billion (£2 billion)

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FNZ


Edinburgh-based fintech FNZ was valued at £1.65 billion in October 2018 when Al Gore's Generation Investment Management and pension fund Caisse de Depot et Placement du Quebec bought stakes in the firm from investment groups HIG Capital and General Atlantic.

The company provides major financial institutions with multi-channel services that span the entire wealth management value chain, from the digital user experience and portfolio management to back-office trade execution, settlement and investment administration.

FNZ was founded in New Zealand in 2003 but moved its headquarters to Scotland in 2012. More than 350 of its 1,500 staff now work in its base in Tanfield, Edinburgh.

Valuation: $2.2 billion (£1.65 billion)

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Checkout.com


Checkout.com reached a valuation of almost $2 billion (£1.5 billion) after raising $230 million in what was the largest ever Series A funding round for a fintech in Europe and globally the third largest of all time. 

The company provides cross-border payment solutions to clients including Samsung, Deliveroo and Transferwise but had attracted little press attention before announcing the Series A investment, its first-ever funding round.

It began life in 2009 under the name of Opus Payments before relaunching as Checkout.com in 2012. Founder Guillaume Pousaz said the new capital would be used to increase the speed at which his company rolls out new products.

Checkout.com's Series A investment round takes the European record from another UK fintech, the challenger bank OakNorth, which hit the top spot when it raised $200 million in 2017.

Valuation: $2 billion (£1.5 billion)

Deliveroo


Deliveroo was valued at $2 billion in September 2017 after raising $385 million from a Series F funding round led by US fund managers T. Rowe Price and Fidelity.

The food delivery service was founded in 2012 by William Shu and Greg Orlowski. Investment banker Shu had grown sick of the convenient dining options available at the time and recruited his developer friend Orlowski to help design an alternative. 

The company first became a unicorn in August 2016 after a $285 million funding round. It's now rumoured to be an acquisition target for Uber.

Valuation: $2 billion (£1.55 billion)

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Babylon Health


Digital healthcare provider Babylon Health reached a $2 billion valuation in August 2019 after raising $550 million in an investment round led by Saudi Arabia's Public Investment Fund (PIF), which is investing $200 million in the company.

The London-based startup is the creator of GP at Hand, a mobile app that provides AI-powered diagnoses and online consultations with doctors that has been publicly endorsed by Health Secretary Matt Hancock. Paul Bate, the company's director of NHS services told Techworld in April that the system facilitates, rather than replaces, doctor-patient interaction.

"We know that something like 90% of GP appointments can be safely carried out without the need for the GP and the patient to be in the same room," he said. "That's much better for the person using the service because they don't have to travel and it's also great for the GPs. It's a better experience for them."

"Now, there are exceptions. It's digital-first, not digital-only. If you're a woman who needs a cervical smear for cancer screening, then that is a face-to-face appointment straight away, and there is zero point in us doing anything digital for taking blood, for example. But the vast majority of the time, you can do things digitally, so we ask. That's the model."

Valuation: $2 billion (£1.55 billion)

Read next: Babylon Health director of NHS services plans ambitious UK expansion

Improbable


Improbable earned a $2 billion valuation in July 2018 after raising $50 million from Chinese tech giant NetEase.

Improbable has built a platform called SpatialOS that can be used to build vast virtual worlds for video games and other areas that would benefit from advanced simulations, such as city planning.

The company was founded in 2012 by Cambridge University computer science graduates Harman Naural and Rob Whitehead and former Goldman Sachs analyst Peter Libka. It first reached unicorn status in 2017, after raising an eye-popping $502 million from SoftBank.

Valuation: $2 billion (£1.55 billion)

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Oxford Nanopore


Oxford Nanopore earned a $1.5 billion valuation in October 2018 after US biotech group Amgen invested $66 million in the gene reading company.

The Oxford-based company produces gene sequencing machines that can electronically analyse DNA in real-time at an affordable price.

Dr Gordon Sanghera, Dr Spike Willcocks and Professor Hagan Bayley spun the company out of Oxford University in 2005. It has since expanded to satellite offices in New York, Shanghai, and both Cambridge, Massachusetts and Cambridge in the UK.

Valuation: $1.5 billion (£1.2 billion)

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Revolut


Fintech company Revolut became a unicorn in April 2018, after a $250 million funding round that valued the company at $1.7 billion, fives times what it was worth a year earlier.

The company was founded in 2015 by CEO Nikolay Storonosky, a former Credit Suisse trader, and Vlad Tatsenko, who previously spent ten years building financial systems at investment banks.

The startup is most popular for its payment card that offers fee-free global spending and international money transfers at the interbank exchange rate, but has since expanded into many financial products. It is yet to receive a full UK banking license.

Valuation: $1.7 billion (£1.3 billion)

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Graphcore


AI chipmaker Graphcore was valued at $1.7 billion (£1.3 billion) after raising $200 million (£158 million) from a Series D funding round led by British venture capital firm Atomico and Belgian investment holding company Sofina. BMW and Microsoft also contributed to the round.

Graphcore's trademark Intelligence Processor Unit (IPU) cards and Poplar software are designed to support multiple machine intelligence applications, from self-driving cars to smart assistants. The company claims they lower the cost of using AI both in the cloud and in data centres while increasing performance and efficiency by between 10x to 100x.

The Bristol-based startup was founded in 2016 by CEO Nigel Toon, the former CEO of silicon chip companies Picochip and XMOS, and CTO Simon Knowles, an engineer and entrepreneur. The duo previously cofounded 3G cellular modem chip company Icera, which they sold to NVIDIA in 2011 for $435 million (£344 million today).

Valuation: $1.7 billion (£1.3 billion)

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Darktrace


Darktrace reached a valuation of $1.65 billion in September 2018 after raising $50 million in a Series E round of funding.

The cybersecurity company was founded in 2013 by a team of Cambridge University mathematicians and cyber intelligence experts from the US and UK with the aim of leveraging AI techniques to better protect companies from advanced cyber attacks.

The Cambridge-based firm first became a unicorn in May 2018, after Vitruvian Partners bought out some existing investors in a secondary round of financing that valued the business at $1.3 billion.

Valuation: $1.65 billion (£1.3 billion)

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TransferWise


TransferWise is a rare breed even by the standards of the species, as the unicorn posted a profit for two years in a row.

The money transfer firm was founded by Taavet Hinrikus, the first employee of Skype, and Kristo Kaarmann, a financial consultant. The Estonian entrepreneurs got the idea for the company from their own frustrations with the cost and complexities of international money transfers.

TransferWise hit unicorn status in May 2016, after a $26 million funding round that valued the company at $1.1 billion. That valuation rose to $1.6 billion following a November 2017 funding round of $28 million. 

Valuation: $1.6 billion (£1.2 billion)

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Blue Prism


RPA vendor Blue Prism became a unicorn in February 2018 after reaching a market value of $1.3 billion

The Merseyside-based company was founded in 2001 and claims to have coined the term "robotic process automation". Its software robots are trained to automate back-office clerical tasks done in applications including CRM, ERP, HR, billing, claims management, customer service, financial management and transaction processing.

Blue Prism has rapidly grown in value since it listed on the London Stock Exchange in 2016 with a market capitalisation of £48.5 million, a testament to the RPA boom that the company has helped to propel.

Valuation: $1.3 billion (£1 billion)

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Brewdog


Brewdog earned unicorn status in April 2017 after the founders of the craft beer maker sold a 22 percent holding in the company to US-base TSG Consumer Partners at a valuation of £1 billion.

The Scottish brewer was founded in 2007 by former schoolmates James Watt and Matt Dickie, who made the first beers in Watt's garage. It's the only business on our list of unicorns that isn't a tech company.

Valuation: $1.2 billion (£1 billion)

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The Access Group


Business software vendor the Access Group reached unicorn status in April 2018, after private equity firm HG made an investment of approximately £30.9 million in the company at an enterprise value of £1 billion.

The London-based company was founded in 1993 and grew to become one of the UK’s few private equity-backed unicorns after 10 years of uninterrupted growth built on an aggressive acquisition strategy and a productive development team.

Valuation: $1.2 billion (£1 billion)

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BenevolentAI


BenevolentAI dropped down our list in September 2019 after The Times reported that the firm has secured an investment from Singapore-based sovereign wealth fund Temasek in a deal valuing the company at $1 billion - just half the valuation it reached the previous year.

The startup uses artificial intelligence technology to develop new medicines for hard to treat diseases. It was founded in 2013 by Ken Mulvany, who previous ran another a biotech company called Proximagen.

Mulvany claims that Benevolent AI can outperform traditional drug discovery by automatically analysing biomedical information to quickly identify the cause of a disease and the compounds that can treat it, drastically shortening the drug development process.

Valuation: $2 billion (£1.55 billion)

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Matchesfashion


Matchesfashion became a unicorn in September 2017 when private equity firm Apax Partners acquired a majority stake in the company in a deal that valued it at $1 billion.

The luxury online retailer was founded in 1987 by husband and wife Tom and Ruth Chapman. It began life as a single brick and mortar store in Wimbledon, London but now generates 95 percent of its revenue online.

The Chapmans bagged a reported £400 million from the sale of their designer empire. They remain as shareholders in the company and now hold an advisory role.

Valuation: $1 billion (£778 million)

Read next: These UK fashion tech startups will help you dress better 

Immunocore


Immunocore was valued at almost $1 billion in July 2015 after raising $320 million in the biggest ever private financing round for a European biotech company. Additional investment of $40 million from the Bill & Melinda Gates Foundation in September 2017 increased its valuation further.  

The Abingdon-based company develops T-cell receptor (TCR) based biological drugs that can treat cancer, viral infections and autoimmune diseases by harnessing the body's immune system to kill diseased cells.

Immunocore began life in 1999 as Avidex, an Oxford University spin-out. Avidex was acquired by Medicine AG in 2006, which split into two sister companies, Adapatimmune and Immunocore.

Valuation: $1 billion (£778 million)

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