It's possible they have commercial relationships with the vendors that back those other OSS projects. It's common for such vendors to build a discount into cont

It's possible they have commercial relationships with the vendors that back those other OSS projects. It's common for such vendors to build a discount into contracts in exchange for promotional support. Also, corporations are not homogenous entities. Perhaps other people in the company would have had the authority to say yes. From what I've seen, there's very little incentive for any company to reveal the technologies -- FOSS or otherwise -- that they use, unless it's to attract job candidates or to position the company as a technological leader in preparation for a funding round. In either case, it's gonna be hype technologies that get on the website: Hadoop ten or so years ago, NoSQL five to seven years ago, some kind of distributed log three to five years ago, and so on.