Here is a patent application that could make it into production, more sooner than later.
Canon patent application in Japan 2017-16156 describes the optical formula for an EF 17-35mm f/4-5.6 IS STM lens. Since Canon started to build non-L, STM lenses for their full-frame cameras, it was to expect that this popular focal length would follow. We usually point to the fact that most patent never make it into production. This one may be different.
- focal distance: 17.50 25.12 34.09
- f numbers: 4.00 4.85 5.88
- half field angle (degree): 51.03 40.73 32.40
- image height: 21.64 21.64 21.64
- length of the lens: 130.88 128.52 134.05
- BF: 37.60 49.75 64.06