Granted Patent
Utility
US 6,607,042 · App. 09/858,954
Method of dynamically controlling bottom hole circulation pressure in a wellbore
Inventors:
Carel W. Hoyer, Robert Graham, Adrian Steiner
Patented Case
View Patent ↗
Granted: Aug 19, 2003
Filed: May 17, 2001
Inventors
Carel W. Hoyer
Robert Graham
Adrian Steiner
Assignee (at issue)
Precision Drilling Technology Services Group, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.