It’s the license type that matters, not how development is funded. Postgres’ license is similar to BSD so even if Microsoft made and was the sole developer and

It’s the license type that matters, not how development is funded. Postgres’ license is similar to BSD so even if Microsoft made and was the sole developer and sold it, anyone could distribute or sell it or whatever regardless of who contributes. Similar to Elastic’s old license and why Amazon was legal in what they did. Amazon (and most all large companies these days) do a ton of OSS dev, but that doesn’t matter. The license of the various software counts.