Other companies are likely to follow in Campaign Monitor's footsteps as the U.K. economy has very strong fundamentals, according to Richard Wilson, CEO of TIGA, the U.K.'s games industry trade association.
"We have relatively low rates of corporation tax and overall a relatively low burden of taxation. We have a highly skilled workforce and the labour and product markets are lightly regulated. Those things are not going to change substantially," he told CNBC during a phone interview.
"For those reasons, I think foreign direct investment will continue to be at a very high level into the U.K."
Following the Brexit vote, other countries have attempted to become more attractive to start-ups in particular, however. Notably, France has upped efforts to appeal to tech companies and earlier in the year, Berlin advertised around the streets of London in an attempt to court U.K. start-ups.
But in the face of increased competition, there are some things the U.K. can do to prevent its start-ups from being poached.
"The first thing to do is encourage an environment that is favourable to start-ups," suggested TIGA's Wilson. "We've got a great tax regime to encourage start-ups. I think, secondly, we've got to make sure we have an overall tax system that is favourable to growing businesses."
He stressed it was also important to have a good provision of access to finance for start-up companies.
"It's a question of making sure that people who want to set up a business (or) people who come out of university, for example, to create a start-up or work in a start-up, that they have the opportunity to do so," he added.
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