Story: IBM's open patents are just the first step
I hate tio burst Ricardo's bubble, but it won't stop others from litigating against Open Source. It means that anybody using code which impinges on the IBM Patents and releasing the resultant code as Open Source, won't be litigated against.
If you impinge on patents from Microsoft's stable (as an obvious example), then you will still probably face litigation (depending on how big you are and how much money they think your product will make.
It also doesn't help small companies writing bespoke software which isn't open source (their customers may not want their trade secrets revealed to all and sundry).
And the problem for most small companies is that their customers won't pay for a couple of years of patent research to ensure their programs aren't infringing any patents, their first knowledge of infringing a patent will probably be when the lawyers come-a-knocking.
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