IANAL, but I don't think he's claiming he doesn't own the business, but that the "offers for sale a variety of products and services designed to circumvent and bypass Nintendo's TPMs" is wrong. The only argument I can see at this point is "The TPM ceases to be Nintendo's after the customer purchases it". I have no idea if that's his angle or if it's a solid argument.
IANAL, but I don't think he's claiming he doesn't own the business, but that the "offers for sale a variety of products and services designed to circumvent and bypass Nintendo's TPMs" is wrong. The only argument I can see at this point is "The TPM ceases to be Nintendo's after the customer purchases it". I have no idea if that's his angle or if it's a solid argument.