Here’s a collection of Leica M lens spec sheets I’ve collected. Most of them are from Leica. However, Leica seems to have a habit of pulling down spec sheets when lenses are discontinued, so I’ve gather some of the others from elsewhere. I’d be very interested in getting a copy of the 90 Summicron pre-ASPH lens sheet if you have one. You can email at tgray at this domain.
Lenses are sorted by focal length then by max aperture, then by date of release.