A startup using artificial intelligence (AI) to tackle the proliferation of fake news and extremist content online will expand after closing a $1m (£720,000) seed funding round that attracted major US backers. London-based Factmata's funding round was led by tech entrepreneur Mark Cuban, but also attracted high-profile investors such as Twitter co-founder Biz Stone, internet entrepreneur Sunil Paul and, more recently, Craigslist founder Craig Newmark. The company will put the cash towards research and development, product development and expanding its team beyond machine-learning specialists. The round was initially closed last August but soon reopened to close formally in the last couple of weeks. Read more: Twitter fails to give MPs "straight answers" on Russian influence on Brexit "Every day there's an article or there's someone talking about fake news at the World Economic Forum, so I wanted to keep the round open so people could come in quite late in the process," founder and chief executive Dhruv Ghulati told City A.M. Factmata is developing both business and consumer-facing products, such as an anti-fake news platform for journalists, researchers and the public to use, as well as collaborating globally with advertisers and businesses that can use its algorithms to sift through and identify fake news, spoof sites and hate content. Ghulati, who was recently named one of Forbes' 30 Under 30 On the B2B side, this would help advertisers find junk content on potential sites they would be advertising on.