The news comes as festival organisers recently announced plans to drop the 'international advertising festival' strap line replacing it for 'international festival of creativity'.
The move came in response to feedback from festival goers.
In 2009, the first year of PR award entries, Hill & Knowlton held its first PR seminar at the event, as well as the first ever Cannes Lions 'tweet up', with Twitter co-founder Biz Stone, to highlight the importance of social media.
Hill & Knowlton chief marketing officer, Tony Burgess-Webb, said: 'Creativity is fundamental to effective communications and Cannes Lions is the epi-centre for creativity in communications. By getting actively involved, we have tried to set a lead for the PR industry worldwide.'
In 2010, the festival saw over 8,000 delegates from 95 countries attending the events on offer over the week.