The private equity firm and the two executives joining the board, Advent Managing Partner David M. Mussafer and Managing Director Steven J. Collins, will look to improve the yogawear-maker's performance by improving online capabilities, helping the brand connect with consumers and expanding its global reach, the source said.
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The company currently operates fewer than 300 stores in nine countries.
"Lululemon is a business that we know well and we believe has continued growth potential, both domestically and internationally," Mussafer said in a news release Thursday. The firm declined to comment beyond the release.
Despite the growing popularity of the athleticwear market, Luluemon's shares have been sliced in half from their all-time high of $82.50 in June 2013. The company's troubles began last year when it recalled its luon pants for their potential to pill and become sheer, and became worse after Wilson's comments that the pants weren't meant for all women's bodies.
Its problems have been exacerbated by failing to spark consumer interest in its more fashionable product, and the growth of brands such as Gap's Athleta.