05233767 is referenced by 148 patents and cites 27 patents.

A midsole, partial midsole, or the like, for inclusion in an article of footwear having a flexible, air-permeable top sole, characterized by at least one plug in the heel region having a thickness (height) sufficient to permit significant compression deformation along its thickness dimension accompanied by simultaneous significant bulging deformation in its circumscribing surface perpendicular to the thickness dimension; the deformations occurring solely due to normal walking activity by any wearer of the footwear; and the deformations thereby providing simultaneously for shock-absorption and ventilation during said normal walking activity.

Title
Article of footwear having improved midsole
Application Number
477732
Publication Number
5233767
Application Date
September 27, 1991
Publication Date
August 10, 1993
Inventor
Hy Kramer
1457 Bassett Ave., Bronx, 10461
NY, US
Agent
Sughrue Mion Zinn Macpeak & Seas
IPC
A43B 13/24
A43B 13/18
A43B 13/20
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