Granted Patent
Utility
US 4,648,747 · App. 06/748,786
Integral buoyant riser
Inventors:
Bruce J. Watkins, Albert M. Regan, Bruce L. Crager, Gary L. Fox, Robert C. Houlgrave
Patented Case
View Patent ↗
Granted: Mar 10, 1987
Filed: Jun 26, 1985
Inventors
Bruce J. Watkins
Albert M. Regan
Bruce L. Crager
Gary L. Fox
Robert C. Houlgrave
Assignee (at issue)
Hughes Tool Company LLC
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.