[1] Junkermann is the founder of NJF Holdings, an international investment company with interests in venture capital, private equity, and real estate.
He founded a jewelry store (Schmuck-Kassette GmbH), a real estate company (IFG Gesellschaft für Immobilienbesitz) and a private bank for wealthy clients.
[9] United in Sports and Junkermann's name appeared in the Panama Papers published in 2016 as clients of the law firm Mossack Fonseca.
The board advises the British Department of Health and the NHS on the introduction of modern technologies such as AI and big data in healthcare.
[8][13] In 2024, Junkermann[14] was also the director of Owkin, a start-up that uses AI for drug development and diagnostics, and an advisor to Trilantic Capital Europe, in addition to her work as an investor.
[15] He was previously married to the fashion designer Princess Mafalda of Hesse and his family controls the oil company Gruppo API.