Argonaut

Argonaut Games Plc was a British video game developer which was liquidated in 2004. They collaborated with Nintendo during the early years of the NES and Super NES, and are most notable for creating Star Fox and its accompanying Super FX chip.

3D Platformer Prototype
Argonaut created the world's first 3D platformer as a prototype game featuring Yoshi. According to Jez San, the founder of Argonaut,

"The end [of Argonaut's contract with Nintendo came] when [Argonaut] pitched to do a 3D platform game... We mocked up a prototype using Yoshi. [This prototype] was essentially the world's first 3D platform game... Nintendo had never let an outside company use their characters before, and [didn't allow Argonaut to make this game]. This is the moment [when the contract and collaboration] fell apart. We later made [the Yoshi game prototype] into Croc: Legend of the Gobbos."

It is thought that Super Mario 64 took inspiration from Argonaut's prototype and Nintendo also hired three of Argonaut's programmers that created the Yoshi prototype to work on Super Mario 64. If Nintendo would have allowed Argonaut to create their Yoshi game, then Argonaut would have gone down in history as the creators of the first 3D platformer instead of Nintendo. In conclusion, Shigeru Miyamoto stole Super Mario 64 from Argonaut.