There are about 300 judges each year, and Phil Thomas is in his sixth year as CEO of the festival, so he's been responsible for naming 1,800 judges.
"I've never had anyone say no," he said, "apart from if a baby is due that week or…a death in the family. The thing about being on the jury at Cannes is that it's almost as good for your career as winning a Lion."
For this reason, he says, the number one question he gets asked in every country he visits is "Can we have more judges?" The answer is never easy -- Mr. Thomas is forever seeking a perfectly balanced jury with the right mix of women, agencies from different holding companies, and independent shops.
The first task is to decide how many judges each country gets, by looking at the number of entries and winners over the previous three years in each category. "Obviously, some countries are rock solid like the U.S. and the U.K." Mr. Thomas said. "If you're a country that's entering and winning big in a category, you've earned your right to have a jury member above a country that's not entering and not winning."
There are still many participating countries that have never had a jury member, which is why a "wild card" was introduced a few years ago, allocating two places each year for emerging countries that have talented creatives but aren't mathematically winning enough Lions to earn a jury spot. Last year it was Costa Rica and Lebanon; this year it's Peru and Tunisia.
This year, 92 countries sent entries to Cannes but 40 of those countries submitted fewer than 50 entries, and 21 sent fewer than 10. Once countries have been allocated a judge or judges, Cannes representatives in those countries are asked to send in three recommendations for each jury – they must come from three different agencies, and at least one must be a woman.
Mr. Thomas said, "Then it goes into the mixing machine, and this is where it becomes like a four dimensional jigsaw. It has to be balanced by holding company, by network, and by agency – so every decision affects another decision." There is an automated system, but much of the work ends up being done manually.
"Broadly speaking," Mr. Thomas said, "Our belief is that if you enter into Cannes Lions you would expect the vast majority of the jury to have won Lions, so we try to make that as strict a criteria as we possibly can."
Inevitably there are exceptions. For the newer categories like innovation and mobile, there is no long history of creatives who have won Lions, so some judges are chosen by reputation. And marketers, who this year make up 5 of the 16-person creative effectiveness jury, aren't required to have a Lion under their belts.
For China, which has only relatively recently embraced Cannes but is a hugely important advertising market—and the festival's tenth-biggest entrant this year with 873 submissions-- the rules have to be relaxed a little. "It's a perfect example of where it can be very difficult," Mr. Thomas said, "so we look at [a candidate's] pedigree by counting Spikes Asia and other local and regional awards."
But in the end, there are no guarantees. "When we launch a category, we have to make a judgment call about which countries should be on a jury," he said. "For the design Lions, we assumed Italy would win, but after three or four years it still hadn't won enough, so it came off."
And in case you're wondering which countries get the most judges, the top 10 countries this year by entries are the U.S., Brazil, the U.K., Germany, France, Australia, India, Canada, Japan and China.