Granted Patent
Utility
US 4,725,991 · App. 06/868,918
Method for controlling blasting operations
Inventors:
Otto E. Crenwelge, Jr., Timothy A. Peterson
Patented Case
View Patent ↗
Granted: Feb 16, 1988
Filed: May 29, 1986
Inventors
Otto E. Crenwelge, Jr.
Timothy A. Peterson
Assignee (at issue)
SHELL OIL COMPANY
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.