As patent law continues to evolve, so does the doctrine of pith and marrow in patent infringement cases. This doctrine is an important concept that addresses the issue of a patent claim's core, essential elements and how they relate to the claims of infringement.

The pith and marrow doctrine, also known as the substance of the invention doctrine, is a tool used to determine whether or not a particular product or process infringes upon a patent claim. It involves a careful analysis of the patent claim to determine its essential features, and then compares those features to the allegedly infringing product or process.

In essence, the doctrine of pith and marrow requires courts to look beyond the literal wording of a patent claim and instead focus on what the invention actually does. This is important because many patent claims can be written in a way that is intentionally vague or overly broad, which can make it difficult to determine exactly what the patentee is claiming as their invention.

For example, suppose a patent claim is written to cover a "device for moving objects from one location to another." At first glance, this claim could be interpreted to cover a wide range of possible devices, from a simple conveyor belt to a complex robotic arm. However, by applying the pith and marrow doctrine, a court could determine that the essential feature of the invention is the ability to move objects in a specific way or using a particular mechanism.

In one of the recent Judgement passed by the Hon'ble High Court of Delhi , in relation to a Patent pertaining to Automatic Tube Cleaning System, the Hon'ble High Court of Delhi has once again applied this doctrine to render the Judgement. The facts of the case and the Judgement has been detailed herein below:

The Subject Matter Patent:

IN 382118 in respect of an Automatic Tube Cleaning System (ATCS). This is an invention as claimed by the Plaintiff is system by which tubes and ducts in air-conditioning system are kept clean.

The Patent was granted on 18.11.2021 with effect from 13.04.2012.

The Essential Feature Of The Subject Matter Patent:

A system comprising, inter alia, of at least:

1. Two collectors.
2. Two pumps.
3. One trap.
4. One sorting system
5. One counting system.

Defendant Impugned System:

1. One Pump
2. No Sorting System
3. No Counting System

The Bone Of Contention:
The Plaintiff alleged that the Defendant has copied the essential feature of the subject matter Patent.

On the contrary, the Defendant highlighted the differences between both the competing products of the parties.

This argument of the Defendant was sought to be disputed by the Plaintiff the incidental differences between the AFCS and ATCS notwithstanding, the pith and marrow of the ATCS stand replicated in the AFCS; ergo, patent infringement has occurred.

The Issue At Hand:

• What is Pith and Marrow Doctrine and how it has to be evaluated?

 

Pith And Marrow Doctrine:

The Court has to outline the essential feature of the subject matter Patent, i.e. the Pith and Marrow of the Patent. In the other words , this doctrine says the necessity of pointing out the essential feature of the subject matter Patent. Pith and Marrow of the Patent simply refers to essential features of a Patent.

How The Pith And Marrow Of A Patent Can Be Outlined?

In order to appreciate the essential feature of Patent, it is not proper to read claims of Patent first and then the specification. Rather the proper way is to read the description of the Patent first and then the claims.

Dichotomizing the claims and the accompanying specifications is, therefore, contrary to the most fundamental canons of patent law.

Pith And Marrow Of The Subject Matter Patent:

All the afore mentioned element as mentioned in Para No.9 of the Claim are unalienable part of the subject matter Patent.

From reading of the summary of the invention as provided by the plaintiff itself in the complete specifications of the suit patent, the Hon'ble Single Judge reached on the conclusion that two collectors having two separate functions, two pumps, a Ball Trap, a counting system, a sorting system and an electronic controller are identified and underscored as the essential features of the suit patent.

Even at the stage of reply to First Examination Report, the Plaintiff itself asserted that afore mentioned element to be essential features of the subject matter Patent.

The Judgement:
As all the afore mentioned essential element of the subject matter Patent were missing in the subject matter Suit Patent of the Plaintiff were missing in the product of the Patent, the Court declined the relief of interim injunction for infringement of Patent.

The Comment On Pith And Marrow Doctrine:

Thus we have seen that this doctrine requires outlining the essential feature of the Patent. Once the essential features of the patent claim have been determined, the court can then compare them to the allegedly infringing product or process to see if they are the same or substantially similar. If they are, then the court may find that there has been patent infringement.

The pith and marrow doctrine has been used in a variety of patent infringement cases, including ones involving pharmaceuticals, computer software, and mechanical devices. It can be particularly useful in cases where the patent claim is written broadly or is difficult to interpret, as it allows the court to focus on the actual function of the invention rather than just its literal wording.

One important caveat to note is that the pith and marrow doctrine is not a substitute for a careful analysis of the patent claim itself. While it can be a useful tool for determining whether or not there has been patent infringement, it should not be used to completely disregard the language of the patent claim.

Overall, the doctrine of pith and marrow is an important concept in patent law that helps to ensure that patentees are receiving adequate protection for their inventions. By analyzing the essential features of a patent claim and comparing them to the allegedly infringing product or process, courts can make informed decisions about whether or not there has been infringement, and help to maintain the integrity of the patent system as a whole.

As we have seen that in the present case, the Hon'ble High Court has refused to grant the injunction in favour of the Plaintiff, as the Defendant has not used all the essential features of the Plaintiff's Patent (the pith and marrow of Plaintiff's Patent). This is another aspect that Plaintiff's own admission to FER report helped the Hon'ble Court to outline the essential feature of the subject matter Patent.

The Case Law Discussed:
Case Title: Ecomax Solutions Pvt. Ltd. Vs Energo Building Solution LLP
Judgment date: 20.03.2023
Case No: CS(COMM) 366/2022
Neutral Citation No. 2023:DHC:2334
Name of Court: High Court of Delhi
Name of Hon'ble Justice: C Hari Shankar, H.J.

Disclaimer:
This information is being shared in the public interest. It should not be treated as a substitute for legal advice as there may be possibility of error in perception, presentation and interpretation of facts and the law involved therein.

Written By: Ajay Amitabh Suman, IPR Advocate, Hon'ble High Court of Delhi
Ph no: 9990389539, Email: [email protected]