New Delhi, Aug. 15 -- Alphabet's early SpaceX investment has delivered a more than 100-fold return, and Nvidia is now sitting on a $21 billion stake in Elon Musk's rocket company. The disclosures come as SpaceX rapidly expands its AI business, boosts infrastructure spending and deepens its partnership with Nvidia. Here's why Musk's AI ambitions could turn SpaceX into a major player in the AI infrastructure race.

Alphabet's early bet on SpaceX has already started showing colour. The Google parent said its $900 million investment in Musk's space company in 2015 had grown more than 100 times, with its SpaceX stake valued at around $94 billion as of the end of June.

Alphabet held 551.2 million SpaceX shares at the end of the second quarter,...