Just another example of a Zeiss T* lens made by Tomioka!

Well done on finding that advertisement!  You are almost correct about the lens being made by Tomioka as their workers assembled the basic elements of the lenses but the finishing of the manufacturing process was handled by Zeiss personnel.

The lenses definitely were manufactured at the former Tomioka plant, though they were designed in West Germany, but supervision and quality control of the production was not by Tomioka staff but by Carl Zeiss people.

As you know, Tomioka as a brand ceased in 1983 when it was subsumed into Kyocera, before becoming the Kyocera Optec Company at the beginning of the 1990s - that company still exists. The Tomioka plant was used by both Yashica and Carl Zeiss but the lens lines were quite separate and had different tooling and supervisory staff. Zeiss operated as a stand alone facility within the Tomioka/Yashica, later Kyocera, plant.  R&D for Zeiss T* lenses was carried out at Oberkochen, including those placed into the legendary Yashica/Kyocera T series cameras.

The T4 and T5 cameras still attract very high prices for a plastic compact because of the reliability of the Yashica electronics and the Zeiss T* glass. Looking at the ad, it's amazing to see how clumsy the external design of the original T is when compared with later models like the T4.