The Doctrine of Equivalents: An International and Comparative Perspective

The Yale Journal of Law and Technology recently published an article in memory of the late Sir Nicholas Pumfrey, who unfortunately passed away at the fag end of 2007. A gregarious judge who had a stellar reputation for getting to the root of a technology in a patent dispute even before counsels explained it to him, Lord Justice Pumfrey was also acclaimed as one of the “nicest” UK judges.
The IPKat did a short obituary, which elicited some very touching comments from friends of Sir Nicholas who recounted their experiences with him, some going as far back as his days at Oxford, when he came adventurously dressed in a “sports” jacket. The Times did a piece focusing on his “professional” achievements and the Telegraph did an interesting take on his unconventional “personal” side, recounting that he took off on long motorcycle trips to France to take care of his “bees”. Little wonder then that his judgments carried a lot of sting for those who found themselves on the wrong side of the law.

The Yale article, authored by an international medley of IP judges, practitioners and academics deals with the doctrine of equivalents, one of the most contentious patent law doctrines. The various authors and their respective chapters are listed alphabetically as below:

1. The US position: Martin J. Adelman (Theodore and James Pedas Family Professor of IP law at George Washington University Law School), Dr. Raj Davé (Partner at Pillsbury Winthrop Shaw Pittman LLP) and Dr. Martin Sulsky (Associate at Pillsbury Winthrop Shaw Pittman LLP).

2. The UK position: Lord Justice Pumfrey (UK Court of Appeals), who unfortunately passed away during the course of this article and Shamnad Basheer (Ministry of HRD Professor in IP Law, National University of Juridical Sciences, Kolkata);

3. The German position: Prof. Dr. Peter Meier-Beck (Judge at the Bundesgerichtshof, Karlsruhe, Germany and a Honorary Professor at the Heinrich-Heine-Universität, Düsseldorf) and Max v. Rospatt (an Attorney at Law and Partner at rospatt osten pross, Düsseldorf, Germany)

4. The Japanese portion: Yukio Nagasawa (former Judge of Tokyo High Court and currently a Professor at the University of Tokyo and a Partner at the Haruki & Tokyo-Marunouchi Law Offices, Tokyo).

The abstract states as below:

“The doctrine of equivalents is arguably one of the most important aspects of patent law. The protection a patent confers is meaningless if its scope is determined to be so narrow that trivial changes to a device bring it out of the bounds of the patent. One of the greatest challenges courts and legislatures therefore face in patent law is to create rules for determining patent scope that maintain the protection a patent is meant to confer while still keeping the patent monopoly within reasonable bounds.

Despite the general unity in patent laws among developed countries, the difficulty of this task has led to different results in different jurisdictions. Many jurisdictions have chosen to determine patent scope under a doctrine of equivalents, while others have maintained the position that adequate scope can be found within the meaning of a patent’s claim. Even jurisdictions which agree that a doctrine of equivalents should apply differ significantly in its application. This Article provides an examination of four patent jurisdictions—the United States, the United Kingdom, Germany and Japan—and their separate answers to the question of patent scope.

This Article does not purport to decide which jurisdiction has the right solution, but merely points out that different solutions can be and have been found for the question of equivalents. Although a traditional case of patent infringement under the doctrine of equivalents may find protection under all four jurisdictions, the laws of these countries start to diverge on questions regarding after-arising technology, the essential elements of a patent claim, and equivalents that clearly fall outside the language of a claim. One cannot answer the question, “Does anybody have it right?” without first considering these issues.”


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6 thoughts on “The Doctrine of Equivalents: An International and Comparative Perspective”

  1. dear shamnad,
    nice paper on doctrine of equivalents. altho i am aware of it in the american context, yet it wud be really educative for me to know how similar concepts are applied in germany n japan (as far as india is concerned, its judiciary is yet to reach that level of maturity in patent jurisprudence).
    i ll go thru the yale paper n form my opinion thereafter.
    thnx for bringing it to spicyip. also, i just hope more n more ‘real’ scholars really contribute to your spicyip! in fact, it is for these reasons that i ve started contributing to spicyip (thru my small comments).

  2. (shamnad, wud u be kind enough to DELETE MY EARLIER COMMENT, POSTED HERE JUST A MINUTE AGO? it was the first draft that got inadvertently sent. apologies for that. u pls publish only the following text. thanx.)

    the yale paper was a good food for thought for me. ‘ideally’ n personally, i would ve advocated for the english purposive construction (of claims, buttressed by the specifications/descriptions/ drawings) approach. diplock’s n hoffman’s approaches (but not necessarily of laddie’s) certainly appeal to me a lot. but given the indian judiciary’s (i)immaturity n (ii)inconsistency in the use of discretion (wherever allowed) in general and in patent matters in particular, i feel that the american model would probably lead to better judgments here. although i am fully aware that both the english n the us models require maturity (the former requires a lil more ‘subjective maturity’ while the latter requires somewhat less subjective n more ‘objective maturity’, as the Americans have a penchant for a rather mathematical model of life), which indian patent judges currently lack, yet i am preferring the american model (over the english one) coz that seems to be providing a lil more objectivity; it provides a lil more major reference points/frames; its constructs/concepts (e.g. doctrine of equivalents, prosecution history estoppel, unforeseeable equivalence, etc.) r lil more tangible/comprehensible/easily spelt-out. the english approach of purposive construction (of claims) provides only one major reference point(i.e. concept of purposive construction). also, the english model cannot provide adequate protection against equivalent variants. lastly, despite my personal preference for the english approach (albeit not without caveats), why i wud still prefer the american model is that the immature indian judiciary (in patents field) needs more clear/objective/tangible/simpler/easily spelt-out concepts n constructs where the scope for discretion/latitude is lesser, so that the influence of extraneous (i.e. non-ipr) principles/concepts could be minimized. moreover, i find another advantage in using the american doctrine of equivalents, which has been developed as supplement to the literal/textual interpretation approach, as enshrined in its section 271 of the title 35 of the united states code. but in india, i am advocating this doctrine’s use in a context which in any case, is largely n unwittingly but not consistently, using the purposive construction (contra-distinct from literal/textual) approach itself. so, many of the demerits associated with the american system can be overcome here. although there can be many criticisms of my approach, yet i would anticipate n answer one (that when even the american model presumes a level of maturity that is at least equal to, if not more than, the one required for the english model and hence, then how the immature indian patent judiciary is supposed to be applying it evenly/fairly/consistently?). the answer to this question lies partly in the preceding para of this comment. additionally, i wud only say that my advocated position is what i wish for the indian judiciary to strive for. n unless v strive for better/higher things, v cant even achieve higher things. so, lets aim higher! also, i am sure that Indian judiciary’s learning curve is pretty steep.
    shamnad, these r just my first thoughts on the issue-at-hand. the idea requires lotsa fine-tuning. i wud b glad if i were to hear some serious stuff on the issue from u.

  3. Thanks for this item. I’d be interested in your opinion on how the recent talk of harmonization will affect international patent law. If the movement goes forward, will American standards ultimately prevail in negotiations? Because, ultimately, if a particular standard does become universally applied, then the question, “Does anybody have it right?” will be critical.

  4. Thanks Aditya for your thoughtful comments,

    I personally think we shoudl follow the UK position at this point, as it is a far less complicated standard. and besides, given our fledgling patnet jurisprudence now, we must take extra caution to err on the side of more “notice” to third parties.

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