04562651 is referenced by 161 patents and cites 15 patents.

An improved sole for use with footwear is disclosed. The sole includes at least one layer of material which is adapted to be attached to an upper of the footwear. A distal flex groove is formed in the sole and is coextensive with a medial metatarsal-phalanges line which extends between the first and second metatarsal-phalanges joints. A proximal flex groove is also formed in the sole and extends substantially parallel to a lateral metatarsal-phalanges line which extends along the second through fifth metatarsal-phalanges joints. The proximal and distal grooves join on another at the medial edge of the sole adjacent the first metatarsal-phalanges joint.

Title
Sole with V-oriented flex grooves
Application Number
6/549659
Publication Number
4562651
Application Date
November 8, 1983
Publication Date
January 7, 1986
Inventor
John R Robinson
Newmarket
NH, US
Edward C Frederick
Kingston
NH, US
Agent
Banner Birch McKie & Beckett
Assignee
Nike
OR, US
IPC
A43B 13/08
A43B 13/14
A43B 5/00
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