For Facebook, I know it's because Yann LeCun (their director) is adamant that all their research be open source. For Google, I think their long term play is re

For Facebook, I know it's because Yann LeCun (their director) is adamant that all their research be open source. For Google, I think their long term play is realizing that Facebook will release equivalent research, so in the long run, there's no benefit in having everything be closed source. Rather, if they publish the best papers, then they can claim the title of the "best AI company", which is great branding for other services like DeepMind Health and Google Cloud ML which would otherwise become a commodity. They can also recruit the best talent with this perception. Also, DeepMind doesn't open source jack, they only publish papers, no code. Microsoft probably has a similar philosophy.