By Ali Lyon Last month, the French media giant Havas was stripped of its B Corp certifications after signing a global media buying contract with Shell. Ali Lyon explores what the decision means for the industry Sitting down for a set piece interview with Campaignmagazine, Yannick Bolloré’s breezy mood belied the tricky circumstances in which his firm found itself. The chairman and chief executive of Havas, the world’s fifth largest communications group, went into the interview with the gospel of adland facing a barrage of criticism, much of it from his own industry. News of his group’s flagshi…