Geometric Modeling kernels are very few.
Dassault and Siemens have a duopoly on this through their ASIC and Parasolid Modeling kernel.
Where is China's Modeling kernel?
Edit : Found one!
It uses ZW3D kernel. How unique it is not known.
Edit 2:
Overdrive is a 3D modeling kernel technology with completely independent intellectual property. It originated from VX Corporation in the USA, whose technologies and the core R&D team were acquired by ZWSOFT in 2010.
Overdrive is a collection of 3D modeling algorithms to achieve the consistency of 3D models in geometric shapes and geometric relationships through geometric calculations.
I'm sure there are other companies. I'm glad.