Wolfgang de Limburg Stirum

Apheon (Apheon) is a private equity firm, a subsidiary of Sienna Capital Management SA founded in 2005 by Ian Gallienne. The firm is headquartered in Brussels with additional offices in Milan, Paris and Madrid.

Publihold SA publishes educational, academic and business books. It designs, produces, and sells textbooks and collections for students and teachers. It also provides educational support tools that help in implementing the curriculums. The company was founded by Albert De Boeck in 1883 and is headquartered in Brussels, Belgium.

Keesing Group BV provides publishing services. It offers puzzle magazines in the Netherlands, France, Belgium, Denmark, Germany, Spain, Italy, Sweden, Norway, Hungary, and the United Kingdom. The firm's brands include Denksport, Sport Cérébral, Tankesport, Megastar, Jan Meulendijks, 10 voor Taal, and Win. The company was founded by Isaäc Keesing in 1911 and is headquartered in Amsterdam, the Netherlands.

Sausalitos Holding GmbH owns and operates a chain of leisure restaurants and bars. The company was founded in 1994 by Gunilla and Thomas Hirschberger and is headquartered in Munich, Germany.

Looping Holding SAS engages in amusement parks operation. It also operates aquarium parks, amusement rides, zoos and acrobats. The company was founded in 2011 and is headquartered in Saint-Malo, France.

VPK Group NV engages in the manufacturing and distributing of paper-based packaging materials. Its packaging solutions include customized protective, transit, consumer, cores, displays and promotional packaging. The firm offers logistical, packaging design and innovation, value engineering, retail-ready, printing, branding and customer experience, digital integration, and customer service solutions for consumer goods, food and beverages, industrial, and e-commerce industries. The company was founded in 1935 and is headquartered in Aalst, Belgium.