Yes, an improvement on an existing product can be licensed if your improvement offers sufficient business value.
Can your improvement be developed, manufactured, marketed, distributed, etc at a cost that will yield sufficient profit for the licensee? Can you show a licensee hard numbers to support this contention?
Will there be there sufficient market demand for the improvement? Can you quantify this?
Can you offer the licensee some business advantage? For example, exclusive use of your patented improvement, or a first mover advantage, or trade secret?
Just some things to consider....
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