It is a commonly accepted principle of patent law that two patents cannot be granted to the same applicant for one invention. This follows from the idea of a patent itself, which is a bundle of rights (such as the right to use or the right to license) granted to an inventor for their invention. This bundle of rights is available only for a limited period of time. Once the time period expires, the rights lapse, the invention enters the public domain, and becomes available to the world at large. While the principle is well regarded, there are ambiguities about what can be regarded as multiple patents for the same invention. In the practice of patent law, this is known as double patenting. In India, in particular, double patenting appears to be a grey area, with no explicit provision in law, and no clear interpretive stand on the issue. In the context of relatively clearer positions taken in other jurisdictions, there is a need for debate on double patenting in India.
What is double patenting?
The general rule is that a person can be granted only one patent for one invention. If this rule did not exist, a person could potentially obtain multiple patents on the same invention or inventive concept, and by extension, acquire a monopoly over the same for an indefinite period of time. But this is not the intent of patent law. On the contrary, the purpose of a patent is to communicate to the public certain specific information about the
underlying invention, such as the identity of its owner, the nature of the invention, and most importantly, the duration for which the patent rights are granted. This means that the public is clear about the date on which the invention enters the public domain. The sentiment underlying the general rule is beautifully put in the classic 1897 case of United States of America v American Bell Telephone Company, (167 US 224):
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. It deprives the public of the consideration which it was to receive for being excluded from the free use of the thing during the life of the first patent.
Besides the public, there are other stakeholders who benefit from the general rule. For instance, it saves time and effort for the patent offices, as examining officials no longer have to spend time assessing and examining multiple patent applications with the same subject-matter or the same scope of claims. The existence of more than one patent on the same subject matter could result in multiple infringement 32 proceedings