Denim apparel company Not Your Daughter's Jeans (NYDJ) has sold a controlling interest in the business to private equity group Falconhead Capital for an undisclosed sum.

The California-based company was founded in 2003 by Lisa Rudes-Sandel and siblings Leslie and Kenneth, and also involves father George Rudes.

Currently stocked in department stores including Nordstrom, Bloomingdale's, Macy's and Dillard's, NYDJ also sells to 3,000 speciality stores across the US and in Canada, Ireland, the UK, the Netherlands and elsewhere.

"Our management team and employees have accomplished a great deal in the short five years since NYDJ was founded," said George Rudes.

"The new executive leadership that we are bringing into the company through this transaction will enable us to take NYDJ to a new level and accomplish our long-term business objectives."