User:SteveSims/Storage/Patentleft2

Patentleft licenses are free patent licenses that are licensed to anyone, on the condition licensees to only use them in products that permit royalty-free redistribution of those product's patents under the same terms of the original patentleft patent.

Example
Person A has a patent, and licenses it under the a patentleft license.

Person B has two patents in his product and wants to use Person A's patents that products. Person B also wants to charge royalties for his two patents. He decides to use Person A's patent, but now must provide his patents royalty-free and under the same terms as Person A's.

Person C has three patents in his product and wants to use Person B's two patents in that product, but doesn't want to use Person A's patent. Person C also wants to charge royalties for his three patents. He decides to use Person B's patent, but now must provide his patents royalty-free and under the same terms as Person A's.