Paust, a primeira vez que vi essas lentes fiquei tentado em comprar já que eu queria uma 85mm 1.4 Nikon e a Zeiss custava um pouco menos, fiquei desconfiado e resolvi pesquisar.
Segue o texto retirado da wiki.
Z-series manual-focus SLR lenses
Zeiss produces optically identical manual-focus lenses for multiple SLR lens mounts under the ZE, ZF, ZK, and ZS lines, manufactured in Japan by Cosina to Zeiss specifications.
ZE lenses fit the Canon EOS EF mount. They feature electronic contacts allowing for focus-confirmation, and electric aperture operation as with standard Canon EF lenses.[16]
ZF lenses fit the Nikon F-mount. They are manual-focus designs Nikon AI-S type aperture indexing. Four design variations are designated ZF, ZF.2, ZF-I, and ZF-IR. ZF is the original product line. ZF.2 lenses are CPU-enabled (similar to Nikon AI-P lenses) offering full metering compatibility with the full range of AF Nikon SLR cameras. ZF-I lenses add mechanical locks for focus and aperture, and additional environmental sealing, for industrial applications. ZF-IR lenses are adapted to infrared imaging, with coatings that transmit wavelengths up to 1100 nm, and focus scales marked for infrared.
ZK lenses fit the Pentax K mount. They have no electronics, are manual focus only, KA couplers. Zeiss announced in September 2010 the discontinuation of the ZK line.
ZS lenses fit the M42 lens mount (Pentacon/Practica/Pentax screw mount). By use of mount adapters they can be adapted to most 35 mm bayonet camera mounts including Canon FD and EF, Pentax K, Minolta SR and Sony/Konica Minolta/Minolta A mounts (with the exception of Nikon F mount), usually losing open-aperture-metering, multi-segment metering, focus confirmation, automatic flash zoom capabilities as well as some built-in shake reduction performance and EXIF data accuracy.
http://en.wikipedia.org/wiki/Carl_Zeiss_AGSe você procurar por reviews dessas lentes todos irão afirmar que a serie Zeiss T foi fabricada no Japão pela cosina assim como a serie AG é fabricada pela Sony.
