Granted Patent
Utility
US 5,376,697 · App. 08/081,495
Drag reducers for flowing hydrocarbons
Inventors:
Ray L. Johnston, Larry Fry
Patented Case
View Patent ↗
Granted: Dec 27, 1994
Filed: Jun 21, 1993
Inventors
Ray L. Johnston
Larry Fry
Assignee (at issue)
Conoco 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.