523991  Trust, Fiduciary, and Custody Activities 

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).

The data published with NAICS code 523991 include these parts of the following
SIC industries:

     6091         Nondeposit trust companies
     6099 (pt)  Escrow & fiduciary agencies
     6289 (pt)  Securities custodians & securities transfer agents
     6733 (pt) Other trust, fiduciary, & custody activities