Why are tech companies so valuable? Matt Cox reports.

Snap Inc - the owner of Snapchat - has caused quite a stir after the company has been valued at up to $25bil in an IPO filing. Snap is aiming to raise around $3bil in an initial public offering, expected in March. It would make it one of the largest US tech IPOs in years, but some disagree with the valuation. Indeed, Snap Inc said it "may never achieve or maintain profitability"; so why are tech companies so valuable, and have such investor appeal? Share Radio's Matt Cox put the question to Adrian Lowcock, Investment Director at Architas.