IP Addresses have not proved very reliable in the past and are far more likely to be Spoofed or similar in the future particularly if the only Evidence Required is them.
Not something I would want to see adopted by anyone let alone the Legal System which already has enough problems. We don't need to make things worse.
As for Reengineering any Software it's not currently possible as even simple things like Dongels has been overcome for Copy Protection Purposes and that is by no means as necessarily Secure as some think it is.
While I adamantly Disagree with the Concept, Intellectual Property Theft is currently controlled to some extent by the Legal System which sort of works to some sort of Degree. The reality however is that anything can be reduced to Source Code reengineered and do what you like if there is someone motivated enough to do it. It's not restricted to Computers or Programming it's a Human Condition and there is currently no solution.
Of course if we where to do away with the Artificial Concept of Money and Power the need to do things like Reengineering Software for different purposes to what it was intended for, for nefarious Actions wouldn't exist as there would be nothing to gain from it but I honestly can not conceive of something like that happening any time in this society.
Many things are actually Improved or Created by altering Software and even M$ accepts this as they have made available Developer Editions of the Kinect Software to be altered and produce software that does things that they can not conceive of doing.
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