Marvel and Pixar never released a standalone movie...
But LFL - on the other hand - retained and financed nearly all their movies and simply used paramount, Fox, etc for distribution...that was just not wanting to sweat the “small” stuff.
It will be interesting to see how they consolidate - for sure - down the road.
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Iron Man (2008 film) - Wikipedia
In November 2005, Marvel Studios worked to start development from scratch,[44] and announced Iron Man as their first independent feature, as the character was their only major one not already depicted in live action.[9]