Patent application for 400mm f4, 500 f5.6, 600mm f5.6 and 800 f6.3 tele-lenses

Thanks for the heads up. The lenses have been designed to be lightweight by having the elements behind the front one to be far back and small to reduce weight. The aperture of the nominal 400/4 may just squeeze into 95mm, although the current EF 400mm f/4 DO ii is of similar size and too large for a 95mm filter. I'm interested, just.