After graduation, she joined the family business,
The DeBartolo Corporation, and became its executive vice president. In 1991, following the championship, she sold the Penguins to assist the DeBartolo Corporation, which was facing challenges in the aftermath of the real estate collapse of 1987. Denise became operating head of the 49ers in 1999 after her brother,
Eddie Jr., was convicted of failing to tell authorities that former Louisiana governor
Edwin Edwards attempted to extort him. Although Eddie could have resumed control of the 49ers after a year, he decided instead to turn his controlling stake in the team over to Denise in return for other portions of the family interests. Despite a years-long perception that the league forced the transaction, Eddie revealed in a 2016 interview that he decided to give the 49ers to his sister and brother-in-law to focus on his family. She and her husband ceded day-to-day control of the 49ers to their son,
Jed York in 2008. However, they remained principal owners on paper until 2024, when Denise sold enough equity to her son to make him principal owner in name as well. On May 24, 2018, the York family, via 49ers Enterprises (the business arm of the
San Francisco 49ers), bought shares in English
association football club
Leeds United to become a minority investor. 49ers Enterprises eventually completed a full takeover of Leeds United on June 9, 2023. ==Personal life==