Thirteen parents, including six entrepreneurs, have pleaded guilty to facilitating their children's admission to selective colleges and universities through bribery and other forms of fraud, the U.S. Department of Justice announced on Monday. Actor Felicity Huffman was also included in a larger report outlining the guilty pleas.

Some of the entrepreneurs are relatively well-known. Jane Buckingham is the founder and president of Trendera, a boutique marketing firm that works with companies like Gap, Target, Condé​ Nast, and HBO. Peter Jan Sartorio founded PJ's Organics, which sells frozen burritos. Gregory Abbott is the founder and chairman of International Dispensing Corporation, a New York City-based food and beverage distribution and packaging company.

Others founded lower-profile businesses. Robert Flaxman is the founder and CEO of Irvine, California-based Crown Realty & Development. Marjorie Klapper co-founded M&M Bling, a fine jewelry boutique store in Menlo Park, California. Devin Sloane is the founder and CEO of WaterTalent, a drinking- and wastewater systems compliance firm.

Each of the six founders was charged with "one count of conspiracy to commit mail fraud and honest services mail fraud," according to the Department of Justice. In total, they paid $530,000 to scandal facilitator William Singer for illegal schemes to help their children get into colleges.

The charge carries a maximum sentence of 20 years in prison, three years of supervised release, and a fine of $250,000. Plea hearings haven't yet been scheduled.

News of the scandal first broke on March 12, when federal prosecutors charged 50 people with various fraud and financial crimes. Others alleged to have paid Singer for illegal services include actor Lori Loughlin and her husband, Mossimo Giannulli, founder of fashion company Mossimo. Neither Loughlin nor Giannulli has yet to enter a plea.