The PR value to Microsoft of making him whole, and of reinforcing the impression of a newly ethical and positive force in the community, would have positively dwarfed the fraction of a rounding error it would have cost to do so. This was such a no-brainer that it's malpractice on somebody's part to have let it come to this. It doesn't matter that they're within their rights under the Apache license. Banal, tone-deaf, emergent corporate amorality shouldn't be the touchstone of the new Microsoft.