Granted Patent
Utility
US 6,323,157 · App. 09/463,533
Base oil for well fluids having low pour point temperature
Inventors:
Joel F. Carpenter, Jose Toye
Patented Case
View Patent ↗
Granted: Nov 27, 2001
Filed: Jan 25, 2000
Inventors
Joel F. Carpenter
Jose Toye
Assignee (at issue)
BP Corporation North America 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.