IP Library › Granted Patent US 5,474,400
Granted Patent Utility
US 5,474,400 · App. 08/156,016

Radon remediation in form-drain apparatus

Inventors: Christopher Kliefoth, Alton F. Parker
Patented Case View Patent ↗
Granted: Dec 12, 1995 Filed: Nov 23, 1993
Inventors
Christopher Kliefoth
Alton F. Parker
Assignee (at issue)
CERTAINTEED 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.

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 5,474,400
App. No.
08/156,016
Filed
1993-11-23
Granted
1995-12-12
Kind
A