IP Library Granted Patent US 6,789,421
Granted Patent Utility
US 6,789,421 · App. 10/044,088

Density-based fuel indicator system for fuel cells

Inventors: Makarand Gore, L. Mann
Patented Case View Patent ↗
Granted: Sep 14, 2004 Filed: Jan 11, 2002
Inventors
Makarand Gore
L. Mann
Assignee (at issue)
Hewlett-Packard Development Company, L.P.

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.

Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 6,789,421
App. No.
10/044,088
Filed
2002-01-11
Granted
2004-09-14
Kind
B2