1991年第2版GPL的设计，同样是为了防止持有专利者利用他们的专利权以某种会使软件变得非自由的手段强加许可协议给重发布者。
GPL version 2, in 1991, was designed also to prevent patent holders from using their patents to impose licenses on redistributors in a way that would make the software non-free.
许可的第二种用途是在专利权、版权和商标权的情形中，所有者(以许可的形式)将制造、复制、买卖其知识产权的权利授予另一当事方。
The second use of licensing is in patent, copyright and trademark cases whereby authority (in the form of a license) is granted by the owner to another party to make, reproduce, buy or sell the item.
然而，专利权持有者没有被要求使用或许可其技术。
However, patent holders are not required to either use or license their technology.
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