On December 31, 2010, after five-and-a-half seasons playing within the Canadiens organization, Lapierre was traded to the Anaheim Ducks in exchange for defenceman Brett Festerling and a fifth-round draft pick in 2012. He made his Ducks debut on January 5, 2011, in a 4–1 loss to the Nashville Predators. The following game, he recorded his first point as a Duck, assisting on a goal by Matt Beleskey in a 6–0 win against the Columbus Blue Jackets. Lapierre played 21 games with the Ducks, recording three assists in that span, before being dealt again prior to the NHL trade deadline on February 28, 2011. He was sent to the Vancouver Canucks, along with forward MacGregor Sharp, in exchange for minor-league forward Joël Perrault and a third-round draft pick in 2012.