This U.S. industry comprises establishments primarily engaged in providing trust, fiduciary, and custody services to others, as instructed, on a fee or contract basis, such as bank trust offices and escrow agencies (except real estate). Cross-References. Establishments primarily engaged in-- ? Managing the portfolio assets (i.e., funds) of others--are classified in Industry 523920, Portfolio Management; ? Performing real estate escrow or real estate fiduciary activities--are classified in Industry 531390, Other Activities Related to Real Estate; and ? Awarding grants from trust funds--are classified in Industry 81321, Grantmaking and Giving Services.