BREWDOG co-founder James Watt has launched a £5 million competition to find the next ‘Unicorn business model’.

The controversial chief executive, who has faced criticism in the past for entering into preliminary discussions with Heineken after condemning the large-scale brewing firm, is now stumping up his own cash to find the "next billion-dollar company".

Watt will reportedly use a “brand-new investment model” where members of the public can vote on the companies in the competition.

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The CEO also revealed that he had been rejected from becoming an investor on Dragon’s Den after his initial bid to appear on the show to secure funding for the craft brewing firm was also rejected in 2009. Instead, Watt appears to have taken his own route to find businesses to invest in.

Branded “The Next Unicorn” search, Watt is reportedly looking for a firm to follow in the footsteps of craft brewery BrewDog, with the help of crowdfunding platform Crowdcube.

European entrepreneurs will pitch to Watt, before he whittles down the entrants with the help of a panel, including Crowdcube CEO Matt Cooper, and Evelyn McDonald, CEO of Scottish Edge - which helped the BrewDog get started 16 years ago.

Watt was “spurred on” by the double rejection from Dragon’s Den to create his own competition, which will see him invest £1 million in three firms, with a further £4 million to be unlocked as the winning companies reach certain milestones.

The National: Watt, left, is the co-founder of BrewDogWatt, left, is the co-founder of BrewDog

Members of the public will then be able to invest in the Unicorns-to-be, doing so on exactly the same terms as Watt, a world-first according to the entrepreneur.

Watt said: “Building and growing businesses is a real passion point for me, and I have learnt so much on my journey getting BrewDog to Unicorn status.

“Given the current economic climate, it’s never been more important to support companies, and I can’t wait to share my experience with some of the brightest business minds across Europe.”

Cooper, Co-Ceo of Crowdcube, added: “We’ve transformed retail investing by creating more pathways for investors to invest in high-performing private companies than ever before. Now, with our partnership, the public can invest alongside leading entrepreneur James Watt in the search for Europe’s next unicorn.”

The submission window for pitches opened on Thursday 30th March and runs to Friday 14th April.

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Shortlisting and judging will take place over a two-week period, before finalists are invited to pitch live to Watt and his panel in London.

The three final companies will then be invited to Las Vegas, where they will receive their funding at BrewDog’s rooftop bar on Friday 26th May.

Following the Vegas announcement, the three winning businesses will be live on Crowdcube.com for the public to invest in the deal too.

On top of a cash injection, the competition winners will also each enjoy an unusual day with Watt to test their “personal relationship and adaptability in unexpected circumstances”.

The scenarios include fishing on Watt’s grandfather’s boat, planting trees in the BrewDog Lost Forest and working a day pulling pints at the beer firm’s Camden bar.