Sileach on notice!, page-8

There's a clear difference there. In the L-Max process, the milled mica is mixed directly with sulfuric acid. In Sileach, there's an upstream lixiviant preparation step in which the sulfuric acid is mixed with some proprietary "reagents and catalysts" prior to contacting the ore. It's the composition of that leaching mixture that's the inventive step - according to LIT, their added reagents allow rapid extraction from all silicates where L-Max only works for mica. Everything downstream appears very generic.

Disclosure: hold both companies, and hope they can kiss and make up and find some arrangement where we all do well.