Shares fell 8.64 per cent to 309p in mid-morning trading as it emerged shareholders including Index Ventures, SM Trust and Vitruvian Partners sold off part of their share for £139m.
But sources close to the deal said placing the shares had "not been easy". The shares were sold at 320p, comfortably above the 260p at which the company floated in April - but investors are likely to have been put off by the idea of early investors in the company, such as Index, reducing their stake so soon after an IPO.
The company, founded in Denmark in 2001, caused controversy when its shares floated right at the top of their range in April, valuing it at £1.47bn, more than 100 times its earnings before interest, tax, depreciation and amortisation, and more than rival Domino's Pizza, which was worth around £916m at the time of the flotation.
The IPO was the most successful of a raft of London tech flotations this year. Others included Boohoo.com, which listed in March but whose shares have languished below its 50p offer price since May, and AO World, whose 285p-per-share offer price was described by one of the banks that handled its IPO as "very punchy". Shares were trading at 250p today.