In philosophy and legal theory, rights can be broken down into positive rights and negative rights. But since philosophers and jurists are involved, the distinction is muddled and the debate takes on more importance than the actual definition. In my mind, the distinction is clear. Positive rights oblige others to act, and negative rights oblige others not to act.
When an inventor is granted a patent, he is given a negative right. He now has the power to prevent others from doing certain things, specifically making, using, or selling his invention. If another decides to make and sell the protected invention, the inventor has the option of suing for infringement and getting an injunction to prevent the infringer from acting. Whether to exercise that right is up to the inventor.
An inventor with a patent does not have the right to make his own invention, only the right to prevent others from doing so. Yes, you read that right.
“Blocking patents” are a common occurrence, and demonstrate when an inventor is prevented from making his own invention. This is a situation where one invention (Invention B) is an improvement over an earlier invention (Invention A), and a separate inventor owns each invention. Invention B cannot be made without also making Invention A, thus Inventor A has a negative right preventing Inventor B from making his own Invention B.
But it works both ways. Inventor B also has a negative right preventing Inventor A from making Invention B. If Invention B’s improvement is so great that it makes Invention A irrelevant, the patents are blocking each other from making the optimal product. In an ideal world, the two inventors reach an agreement to cross-license the blocking patents, allowing each to make Invention B.
The example above highlights the importance of performing a prior art search before pursuing a patent. But it is also demonstrates how patent rights actually work. Patents don’t guarantee the right to produce an invention, but they do give the inventor the right to prevent others from doing so.