Previously supply has exceeded demand for the Tier 2 visa. Around 6,500 went unused in 2013/14 and around 200 went unused in 2014/15.
A separate visa, known as the Tier 1 Exceptional Talent visa, exists for highly skilled technology professionals looking to enter the UK. There are just 200 of these available every year and they're issued by government quango Tech City UK.
However, earlier this year it emerged that Tech City UK gave out just seven of its 200 visas, raising questions about the effectiveness of the visa route.
Other visas exist for technology professionals looking to enter the UK but these have been criticised for attracting the wrong kinds of people. For example, the entrepreneur visa is often wrongly-given to investors.
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