'PANELLED' shank on wrenches

[cgw2also]

Newbie Charlie back for more learnin. I have several wrenches with 'panelled' shanks that have no maker information on them except one and it's a Herbrand. So my first question is was that a design feature that was not patentable  or trademarketable? Was that a design only used by Herbrand and if so were ALL the wrenches in the attached photos made by them?  IF NOT then any ideas/guesses as to who made the wrenches in the photos would be very much appreciated. TIA for your help.

Newbie

[bill300d]

Q1 Shank design has been trademarked by a couple of makers that I can think of all though most don' t unless the design is very distinct.

Q2 The wrenches in your pics all have what is probably the most basic styles of depressed panel. I say styles because there are 3 or 4 different ones there.

Q3 Not only used by Herbrand. I see 3 different brands in your pics Herbrand, the Tru-fit could be Lectrolite or if earlier than 1932 Milwaukee Tool & Forge, and the rest I believe are Vlchek.

[cgw2also]

 WOW! , Thanks very much bill300d, great information.

Newbie Charlie