Regardless of the immoral act, your argument is wrong. A third party willing to pay has no bearing on the morality of an act, doesn't matter how much you try to escape this.
You didn't replied what you do for a living, I'm sure you didn't because you know that there's a very high chance I can show you you don't truly believe that all knowledge must be free. Let me ask you other question then, what's your credit card numbers, expiration date and code, it's just numbers, by your own logic you shouldn't have any claim to own them, therefore you should be okay to share them. The fact that you won't is proof you understand that even if numbers can't be owned, the information numbers convey is a different story.
And no, the companies are not claiming to own math, but to own the algorithm, the math on which those are based is (in general) public knowledge, and even in the cases where it's not, like you said, math is math, others might have discovered it individually. Multiple of those companies might be using the same math independently without realizing it.

