Aldi may appear as if they were a single enterprise with certain store brands or when negotiating with contractor companies. The individual groups were originally owned and managed jointly by the brothers. Karl Albrecht, who died in 2014, retained ownership of Aldi Süd with a personal wealth of €17.2 billion that made him the richest man in Germany. The co-owners of Aldi Nord, Berthold and Theo Albrecht Jr. came close behind at €16 billion. Dieter Schwarz, owner of Lidl and Kaufland came in third, with a fortune of €11.5 billion. Aldi started to expand internationally in 1967, when Aldi Süd acquired
Perekrestok (supermarket chain) connected. In November 2017, X5 introduced machine learning to bolster targeted marketing at the Perekrestok supermarket chain, and developed personalised offers for all members of the Perekrestok Club loyalty program. The company leverages machine learning to group customers into segments based on common features and create offers for them. The system analyses groups of customers and designs personalised marketing campaigns based on demographic and several hundred behavioural factors, such as: frequency of purchases and ticket size, customer preferences, lifestyle fundamentals, acceptable price levels, favourite product categories and preferred shopping hours. Customer sensitivity to offers is predicted using various analytical models.