Olsen Twins Invest in Online Santa Monica Company

Twin actresses and fashion designers Mary-Kate and Ashley Olsen have undertaken the co-chairship of the Santa Monica-based e-commerce company BeachMint.

The duo hold a minority ownership stake in the company and as such have creative and consultative roles in the online retailer after signing as partners and designers for divisions StyleMint, ShoeMint, IntiMint and JewelMint in 2011.

"In our expanded roles as co-chairs of the advisory board, Ashley and I will work closely with BeachMint's management team in this strategic phase of growth to establish the Mint brands as the leading online destination for all things fashion," Mary-Kate said in a statement.

The siblings already have their own brands Olsenboye, The Row and Elizabeth and James. Co-founder and chief executive of BeachMint Josh Berman said in a statement, "Mary-Kate and Ashley are a natural choice to advise on key business, merchandise and design areas as we further scale our women's fashion divisions. The agreement with Ashley and Mary-Kate is the first of a number of significant partnerships we have had in development for some time now."

Other stars have also collaborated with the website to add their own touches. Actress Rachel Bilson and celebrity stylist Nicole Chavez teamed up with footwear designer Steve Madden to launch their own collection for ShoeMint. Alongside this, pop star and actor Justin Timberlake partnered up with his interior designer friend Estee Stanley to create the collection HomeMint.