A patent application covering two optical formulas for both a full frame and APS-C superzoom have surfaced in Japan.
- Full Frame: 28-550mm f/3.5-6.3
- APS-C: 15-300 f/3.5-6.3
I think it's more likely that we see a replacement for the EF-S 18-200mm f/3.5-5.6 IS than a superzoom like this for a full frame DSLR. Though these formulas could be related to a completely different lens.