Vidsy is a technology platform that links brands with content creators to produce original mobile video ads.
The startup founded by Gerard Keeley, Alex Morris and Archie Campbell has so far raised almost $1.8m (£1.39m) in four rounds of funding.
The most recent investment came in March, led by Guardian Media Group, and raised $1.3m (£1m). Other investors are Coral Reef, Force Over Mass and Ascension Ventures.
Vidsy closely scrutinises the potential of each video creator before adding them to its network, where it produces engaging video for advertisers that centrally manage their brand content.
The proprietary technology looks to streamline the entire video process.
Brands have access to video management tools, and analytics provide insights into how their creatives are performing. There are currently around 1,700 UK creators and Vidsy is keen to expand into the US.