In the process of selecting companies for the fund portfolio the investment companies cooperate in addition to or instead of an inhouse-research with external research providers and rating agencies. These research-providers collect and evaluate relevant information about possible investment candidates and their environmental, social and sustainability performance.

Principially there are two approaches:

Providers with their own concept concerning the investigation and evaluation of companies. These providers sell their concepts.
Providers evaluating the companies by using the criteria and methods definied by the company.

Nowadays, most of the research providers use both approaches according to the demands of their customers.