EX-21.1 2 d66380exv21w1.htm EX-21.1 exv21w1
Exhibit 21.1
Subsidiaries of the Registrant
     
    State of
    Incorporation or
Name   organization
Ambar Lone Star Fluid Services LLC
  Texas
Patterson (GP) LLC
  Delaware
Patterson Petroleum LLC
  Texas
Patterson-UTI Drilling Company LLC
  Texas
Patterson-UTI Drilling Co. Canada
  Nova Scotia
Universal Well Services, Inc.
  Delaware
UTI Drilling Canada, Inc.
  Delaware
Patterson-UTI Management Services, LLC
  Delaware
UTICO LLC
  Delaware