The Fine Brothers posted an update video to address some of the controversies sparked by their original announcement / Fine Brothers Entertainment (screenshot)

The brothers' plan has been heavily criticised by some other members of the YouTube community

Popular YouTubers the Fine Brothers have faced a backlash from the YouTube community and fans over their plans to trademark the word “react” and license the 'reaction video' format.

Brothers Benny and Rafi Fine have built up millions of followers and billions of views on their numerous YouTube channels.

They specialise in 'reaction videos', in which different groups of viewers are filmed watching popular viral videos, film trailers and clips of famous figures and asked to give their reaction.

A number of different series on the channel, such as Kids React, Teens React and Elders React, have gained loyal followings of their own, turning Fine Brothers Entertainment from a simple video project into a large business, and making it one of the most popular channels on YouTube.

But the pair have faced criticism recently, after releasing a video in which they announced React World, a licensing scheme that would allow other YouTubers and content creators to make their own videos with the “react” title and the Fine Brothers' graphics and music.

In July last year, the brothers also filed for a trademark on the word “react” with the US Patent and Trademark Office, which would give them and their licensees the sole right to use the word in relation to online entertainment videos that follow the reaction video format.

The Fine Brothers have successfully dominated the reaction video market, but it has been argued that the format existed long before they began producing their videos - this is the point which has spawned much of the online backlash.

Some popular YouTubers have criticised the plan, which they believe goes against the free and open nature of content creation on the internet, with some making parodies of the original React World announcement video or even creating their own reaction videos, in which they respond to the brothers' ambitions.

In a video update posted after the controversy began, the pair stressed that they were not trying to trademark the reaction video genre itself, but just their particular format.

They also said that the React World programme was an effort to help smaller content creators to find success, with the support of the larger Fine Brothers network.

The pair emphasised that their trademark application on the word “react” did not mean they would “run around and start taking down videos.”

However, the Fine Brothers company has been accused of issuing takedown requests to YouTube channels producing similar videos, and the brothers have previously criticised the Ellen DeGeneres show over a segment in which young children were presented with out-of-date technology - something they claimed was too similar to their own format.

Despite the update video explaining their intentions, many former subscribers have unsubscribed from the TheFineBros channel, causing their follower count to dip from over 14 million to 13.9 million at the time of writing.

The Independent has contacted Fine Brothers Entertainment for a comment on the issue, this article will be updated when they respond.