'When I graduated my plan was to become a professor and public intellectual. Hoffman's original plan was to become an intellectual. He grew up in Berkeley and went to Stanford University, where he got a BA in the university's 'symbolic systems programme', an inter-disciplinary study that, according to the university's website, 'focuses on computers and minds: artificial and natural systems that use symbols to represent information.' Then he went off to Oxford to do an MA in philosophy.

But, in 2009, Twitter bought a geo-location business called Mixer Labs, funded by Hoffman, and he got shares in that too. Twitter was about the only major social media pie in which he didn't have a finger.

In 2009, he joined venture capital firm Greylock Partners where he has led investments in Groupon, among others. Hoffman's cash helped start Facebook, Zynga and Flickr. He founded LinkedIn eight years ago and owns 20% of the company. The serial entrepreneur seems to be behind nearly every social media firm now heading to market. Hoffman is first in line to collect on all of them. Facebook's valuation is now approaching $100bn, Groupon is said to be worth $25bn, and all those people playing Farmville have driven Zynga up to $10bn. The increase comes as its peers, including Facebook, online discount service Groupon, and social gaming firm Zynga, line up their own IPOs at ever-increasing valuations.

The share sale will value the whole company at up to $3.35bn (£2bn), significantly higher than the $2bn expected when LinkedIn first filed IPO documents in January.

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