Granted Patent
Utility
US 5,139,946 · App. 07/725,148
Dot matrix membrane cell expansion
Inventors:
Gary W. Howell, Joseph D. Irr, Ara T. Nahapetian
Patented Case
View Patent ↗
Granted: Aug 18, 1992
Filed: Jul 9, 1991
Inventors
Gary W. Howell
Joseph D. Irr
Ara T. Nahapetian
Assignee (at issue)
The DuPont Merck Pharmaceutical 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.