Sigma has patented new L zooms: From 28-100mm f/2.7-4.0 to 20-80mm f/4.0
Image on top shows the 24-10mm f/4.0 design
Sigma has patented the design of fours different zoom lenses:
20-80mm f/4
24-100mm f/4.0
28-70mm f/2.8
28-100mm f/4
via Hi Lows Note