A person is only allowed to get one patent for one innovation. This is still the practise because if this principle didn’t exist, a single inventor may have obtained many patents on a single innovation. This would result in the invention having a clear monopoly. However, it is not the goal of patent legislation around the world. The goal is to give an inventor a set of rights to his or her creation for a set amount of time. Following the expiration of the patent, the invention is released into the public domain for the benefit of the general public.
A patent cannot be awarded twice, as it denies the public from use of patented invention after the original patent has expired. The court held in the case of United States of America V. American Bell Telephone Company: “the thing which the public pays for in submitting to the monopoly created by a patent is the free enjoyment of the invention after the patent expires. To deny to the public this free use of the invention to which it has become entitled under the contract (of patent) is to take away from it a thing of value which it has bought and paid for…. A second patent covering the same invention has this effect. Multiple infringement proceedings for the same innovation could occur from the existence of multiple patents on the same subject matter.
Double patenting is the practise of acquiring or attempting to obtain two or more patents in the same jurisdiction for the same invention by the same applicant. Double patenting is commonly unacceptable in most patent systems around the world. However, the definition of what constitutes duplicate patenting varies by state. Double patenting can occur when there are two or more outstanding applications, or when one or more pending applications and a patent are filed at the same time.
Examining Patent office typically look for three things before bringing a duplicate patenting objection:
- Entity: a duplicate patenting objection can only be made if the applicant or inventive entity of the two patent applications in dispute is the same. At least one of the inventors must be a common inventive entity. Even if the inventor or inventors stated in each patent or application are not same, it would be considered duplicate patenting as long as there is shared ownership.
- The claims in the patents or applications in dispute should be identical or similar. To put it another way, they shouldn’t have assertions that contradict each other. It’s possible that two patents or applications with the same description claim distinct subject-matter, in which case duplicate patenting isn’t an issue. This requirement’s scope and application may differ depending on the jurisdiction.
- The other patent application must be pending or awarded: a conflict of claims or double patenting can only occur if the other application is still active and published, or if it has been granted a patent. An objection of duplicate patenting cannot be raised if the other application was already withdrawn.
In India, there is no explicit provision that states that double patenting is invalid. It can, however, be deduced from Section 46(2) of the Patents Act of 1970 that a single patent is only granted for a single invention. However, if a patent application claims the same invention as another patent by the same applicant, even if the effective date of filing of the application under examination is earlier than that patent, an objection of duplicate patenting may be filed. For instance, if a subsequent application is approved before a previous application, an objection of claims with same ambit could be submitted during the prosecution of the prior application.