Business-to-business marketing agency Transmission has tripled in size since 2019 and now employs more than 350 people worldwide. It has delivered campaigns for the likes of HP, EY and Microsoft. Last year, it opened three offices in America and one in Poland, adding to bases in the UK, Europe, Australia, China, India and Singapore. Transmission began life in 2013 as a London-based marketing agency, and has expanded under the watch of founder and chief executive Chris Bagnall.