IP Library › Granted Patent US 4,643,206
Granted Patent Utility
US 4,643,206 · App. 06/802,920

Cigarette filter

Inventors: Martin L. Reynolds, Dorothy M. Frank, Tilford F. Riehl
Patented Case View Patent ↗
Granted: Feb 17, 1987 Filed: Nov 29, 1985
Inventors
Martin L. Reynolds
Dorothy M. Frank
Tilford F. Riehl
Assignee (at issue)
Brown & Williamson Tobacco Corporation

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Quick Facts
Patent No.
US 4,643,206
App. No.
06/802,920
Filed
1985-11-29
Granted
1987-02-17
Kind
A