The Lululemon founder who invented athleisure is now the company’s harshest gadfly

Lululemon Athletica founder Dennis “Chip” Wilson left the company’s board in 2015, but he has been a thorn in the activewear giant’s side for months, resuming last autumn a years-long campaign in which he has frequently and publicly accused it of becoming a lumbering corporate dinosaur that has lost its edge.

Wilson ramped up that pressure in late December by launching a proxy battle to force the departure of three directors who are up for re-election at its next annual shareholder meeting...