Patent application 201263568 is for a new 16-35mm f/2.8 lens from Canon. The patent also includes calculations for a 17-35mm f/2.8-4 and 16-35mm f/2-2.8 lenses. The interesting part is that Nikon recently also filed a patent for a new 16-35mm f/2.8 lens.
Canon also filed a patent 201247869 in Japan for a 2.0x and 2.8x teleconverters:
