In 1928, León's sons –Gregorio, Numo and Noel– founded Gregorio, Numo y Noel Werthein (GNNW), the company that would end up being the basis of the Group.
At the same time, León's youngest son, Julio Werthein, would embark on a successful career in the banking business, which would facilitate the family's incursion into the financial services industry with the acquisition of the Banco Mercantil Argentina in 1963.
And Leo Werthein, Noel's oldest son, played an important role in the development of the livestock industry and bovine genetics in Argentina. He was the Group's most prominent figure until his death in 2005.
The Werthein Group continued to grow as the third and fourth generations of the family took over and by the end of the 20th century it had established itself as one of the most important locally-owned private holding companies in Argentina.