Through its network of wholly-owned subsidiaries and affiliates in over 50 countries worldwide, Stewart Group (formerly Alex Stewart Assayers) provides customers with independent verification of the quantity and quality of commodity shipments, as well as assessment of samples for mining exploration. The group's business is focused on two main commodity areas: metals and minerals; and coal and solid fuels.

CBPE backed the MBI/MBO of Stewart Group from its owner in November 2006. Since that time, the group has made five acquisitions in Europe, North America and Africa, enhancing its global coverage and service offering.

CBPE realised its investment when the business was acquired by ALS Group in July 2011.