They used to be known as 2nd party titles (like Rare was a 2nd party developer for Nintendo). But I guess people just base it off the publisher now. Although not internally developed by Nintendo, they were funded/published and distributed by them.
I'd say Nintendo put them out as new IPs as they published them and they are exclusive to their platform. Nintendo have still invested in them even if they didn't develop them internally.
Sony have always been very good at putting new IP out there though. It's just a shame a lot of it doesn't become anywhere near as popular as it deserves to be. Heck it used to be known as the SCEI badge of doom if Sony were publishing a game it seemed doomed to obscurity.
RIP Dad 25/11/51 - 13/12/13. You will be missed but never forgotten.
