Well if you goto the following link and then click on Contax and read points 1 and 2. That is all I know.
At the time the Zeiss Ikon was under development, I believe that Kyocera still held the rights to the Contax name, even though there were no new products on the market.
Next, Zeiss doesn't have camera manufacturing facilities. To build cameras is no easy task. In addition to manufacturing space, there also is the investment in equipment, training, additional employees, raw materials, etc.
That's a hefty investment.
It made great sense to go to another company that already had all of this in place, including a track record in making rangefinders.
Remember, Zeiss Ikon made cameras but not lenses. Carl Zeiss made lenses but not cameras. And although the new camera is branded Zeiss, Zeiss still doesn't actually make the camera.
Read this, I find it nice to read. Not exactly answer to OP question, but still...
There are no real secrets today to building cameras and lenses,
the principle issues are the price point in the marketplace,
and how much profit the builder wants to get.
We are familiar with the notion that 80% of perfection can be achieved with 20% of the cost.
Just how close a firm wants to come to perfection is an interesting choice for the makers.
Comparing the policies of, say, Cosina and Leica, my own feeling is that the mechanics of Leica have become
too much a self destructive obsession while Cosina's Voigtlander brand falls short by the narrowest of margins.
The gap between C-V & Leica is great, and the Zeiss commitment to place products in that middle range makes me happy.
Zeiss has over a century's experience with joint ventures. In today's world, it isn't enough to sketch out a lens design on the back of an envelope, you engineer the lens together with the manufacturing process: it is impossible to design a lens without designing the means of making it. THIS is the genius of Zeiss, and the Zeiss-Ikon brand is a testament to the passion and capability of CZ & C-V. Everything that comes from Zeiss-Ikon manufacture meets the criteria of CZ and C-V. It doesn't matter WHERE the manufacturing takes place.
Camera-snobbery is too often a socially tolerated form of bigotry and racism. Design and manufacturing excellence - across political and cultural borders - rely on wisdom and passion, qualities inherent to our species and NOT related to melanin levels or blood type.
The main thing: we need to know that Zeiss is not one company: it started out as Carl Zeiss Optical, in Jena; after Carl Zeiss's death, the owner was its designer Ernest Abbe, who founded the Carl Zeiss Foundation to run it. The Foundation also had many interests, and it organised the amalgamation and acquisition of four camera manufacturers to form Zeiss-Ikon, what can be considered the camera division, but a separate corporate entity.
Zeiss Ikon basically closed up shops in the 1970s, although the Carl Zeiss Foundation still owns the names. Carl Zeiss Optical keeps on going as it is profitable, but it would not be at all economically viable for the Foundation to pour money to start making cameras again: with a lapse of decades they would have to start with a clean sheet of paper and that would be commercially absurd if Cosina already has what 's needed.