In 2007, they announced another line of more contemporary clothing, Elizabeth and James, which is named after their sister and brother.
In 2005, Mary-Kate and her sister purchased the minority shares of Dualstar, taking full control of the company.
The 30-year-old twins were caught getting cozy with their beaus while the New York Knicks took on the Brooklyn Nets at Madison Square Garden on Wednesday night.
Ashley Olsen was all smiles as she showed some PDA with her rumored boyfriend, financier and art collector Richard Sacks.
Olsen then called her security staff in New York to investigate the matter. The next year, the sisters began appearing together in the Badgley Mischka ad campaign.
They also made their foray into the world of high-end fashion by launching a line of their own called The Row in 2006.