liudidi 我上面已经提到了“只要你是唯一贡献者或者得到所有贡献者同意，你怎么干都行”。那你就是同意可以改了。
但这就和那个copyleft.org文档有冲突了。我再贴一遍这个文档7.4.1第一段最后一句：
“A contributor by definition is modifying the code and therefore has agreed to all the terms in the GPLv2, which includes the web of mechanisms in the GPLv2 that ensure the code can be used by all.”
他认为contributor同意了all the terms in the GPLv2。如果贡献者受到GPLv2的约束，那他就没办法改成闭源协议，GPLv2要求再分发时不得限制复制、分发、修改的权力：
6. Each time you redistribute the Program (or any work based on the Program), the recipient automatically receives a license from the original licensor to copy, distribute or modify the Program subject to these terms and conditions. You may not impose any further restrictions on the recipients' exercise of the rights granted herein. You are not responsible for enforcing compliance by third parties to this License.
你从GPLv2改成闭源协议限制了这些就违反了协议。
所以合理的解释就是这个copyleft.org文档说得不对，贡献者不受GPLv2约束。
