What Grygus said.

I've seen more screwball licenses come out of Microsoft than just about anywhere. Some of them are downright hilarious -- they try to open up a codebase for some use, say teaching or self-exploration (no, not that Self), and then trip over themselves with internal inconsistencies trying to F.Y. the FSF.

One of my early observations in looking at free software licenses is that you can tell what the author is concerned about by reading the license. It's what I call fear-greed analysis.

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• FSF wants to free software, and is paranoid about hoarding.
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• BSD/MIT want to promote adoption w/o regard for proprietary/free use, and are concerned about liability (as are virtually all licenses) and/or attribution.
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• Apache wants the above but makes a gratuitous dig at the FSF (intentional retention of the advertising clause).
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• Perl wants confusion to spread freely, with attribution.
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• IBM is paranoid about patents.
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• Mozilla wants to preserve a business model, in as free a framework as possible.
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• AT&T wanted to get anything out the door, and settled on the best license they could wring from their lawyers (Plan9OS)
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• Sun is petrified over losing control (Java II)
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• Apple is like Sun, but with ego problems
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• Corel was concerned with canadian law and minor participation in contracts.
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• The OSL/ASL are concerned about the enforceability of free software licenses without use of contract law.
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• Microsoft is scared shitless by the GPL.
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And so it goes.