My understanding is they have the patents on a test to see if a...

My understanding is they have the patents on a test to see if a cow  carries the a2a2 pair of genes. However other companies also have different tests to find out the same thing. I'm an NZ dairy farmer and our cows have been tested to see which ones carry the a2a2 genes. This same company can now do the same test with a milk sample making it easier. A about half the cows in NZ carry the a2a2 genes so a2 milk could be ramped up very fast. A farmer with multiple  herds  could easily put half of their cows into an a2a2 herd. Alot of dairy farmers here are now breeding for a2a2 genes and the main breeding companies have stopped using a1a1 bulls so the NZ herd will be a2a2 soon and all NZ milk products from any company will be a2a2 possibly disrupting any premium. Any one can sell a2 milk anywhere but can't call it a2 milk in curtain markets (could get around this by calling it non a1 milk or milk from cows carrying the a2a2 gene). All other mammals carry a2a2 genes only so all goats milk baby formula is a2a2. I've also heard some of the big international dairy companies like Nestle are getting into a2 milk.