Top Stories

Post Grant Amendment of Patents

By John Richards
Posted: 24th November 2015 10:48
There is a real life problem in that when filing a patent application one will carry out a search, but it will be a relatively cheap search.  When the patent is granted and becomes important, those who are, or who feel, threatened by the patent carry out a much more expensive search.  This may result in prior art that knocks out part but not all of a claim.  The problem has been exacerbated by recent advances in search technology which means that it is more likely that a search today will find prior art that remained uncovered when the application giving rise to the patent was filed 10 or more years ago.
The issue has come center stage recently in view of the difficulties experienced in making amendments in review proceedings before the patent Trial and Appeal board in the United States and decisions such as those of the U.S. Federal circuit Court of appeals in Fresnius USA Inc. v. Baxter International and the United Kingdom Supreme Court in Virgin v. Zodiac where in the first case the patent office held claims invalid after they had been upheld by the court and in the second claims were narrowed by the European patent Office after they had been upheld by the court such that what had been found to be an infringement no longer fell within the scope of the claims.
A number of issues present themselves:
  • Is there merit to allowing amendments during a law suit or should amendments only be permitted in separate proceedings in the Patent Office?
  • If amendments are to be permitted as part of a law suit, should the amendments apply to those proceedings or only prospectively?
  • What should the role of the patent office be?
  • Should there be total re-examination of the patent or just consideration of clarity and narrowing nature of the amendment?
  • Should there be a role for public intervention in the amendment proceedings?
  • Should the allowability of amendments be discretionary and if so what factors should be taken into account when exercising discretion (for example should a patent owner be penalized for sitting on a claim it knows to be invalid?
  • If amendment proceedings are separate from litigation for enforcing a patent, how should the proceedings interact with each other if a claim is amended in one tribunal after being upheld in the other?
The procedures available for addressing this problem vary significantly from one jurisdiction to another, but none may be totally satisfactory.  For example:
Australiahas some of the most comprehensive legislation relating to amendment after grant which is permitted under a number of provisions:
Either a third party or the patent owner may request that a patent be re-examined.
Where the validity of a patent is disputed in any proceedings before a prescribed court, the court may direct the Commissioner to re‑examine the complete specification.
The patent owner may request the Commissioner to amend the patent by:

(a)  removing a lawful ground of objection; or
(b)  correcting a clerical error or an obvious mistake.
The law provides for opposition to the allowance of any such amendment by “any person” and to facilitate this, any amendment considered permissible by the Commissioner is published in the Official Journal.
Section 105 provides that in any relevant court proceedings in relation to a patent, the court may, on the application of the patentee, direct the amendment of the patent.  Such discretionary power has been used by the courts to refuse amendment in cases where the patent owner has delayed unreasonably in seeking amendment and was obtaining an unfair advantage by maintaining unamended claims.
European Patent Convention
As originally enacted, the European Patent Convention contained no provision for “central amendment” after a European patent had been granted and such amendment was a matter of national law. This changed on December 13, 2007 when EPC 2000 came into effect and opened the door to central post grant limitation to all patents in the bundle of patents arising from a European patent application.
EPC 2000 added new Articles 105a, 105b and 105c which provide the patent proprietor with a means for effecting surrender or limitation of a granted European Patent by way of a single procedure before the EPO rather than having to institute limitation or amendment proceedings in national fora, as was the case previously.  Such proceedings permit the patentee to limit the patent by amendment of claims. Any such limitation will have effect in all designated states and an amended specification will be published.  Under Article 115, third parties may present observations on the amendments proposed in such a procedure but do not have any right to oppose them. Under Rule 95, a request for limitation is examined to check that it is in fact a limitation of the claims and that it complies with the requirements of clarity of the claims and of Article 123 (i.e. that the new claims are “directly and unambiguously derivable from the original text and are not being broadened) There is, however, no examination as to whether the amended claims are novel or possess an inventive step.
Additionally, Article 138 was amended to specify that in proceedings before a national court where validity is in issue, the patentee shall have the right to limit the scope of protection by amending the claims.     
In France, limitation of the claims is possible as a result of a challenge to their validity in court proceedings in the Paris Tribunal de Grande Instance.  In this case, the patent owner must submit amended claims in conformity with the court’s ruling to INPI.  The Director of the INPI has the power to refuse to effect the amendment if it is not in conformity with the court’s judgment.
Since 2009, it has been possible to seek limitation of a French patent or the European part of a French patent by a request to INPI at any time during the life of the patent.  INPI can review the proposed amendment for compliance with the law, particularly on the questions of clarity and whether the proposed amendment seeks impermissibly to broaden the scope of the claim.  If the amendment is allowed, it has retroactive effect back to the grant of the patent.  Proposed amendments are not advertised, but if a third party is made aware of them and submits observations these shall be taken into consideration.
The court hearing an infringement action has the power to stay proceedings if limitation is being sought in proceedings before INPI.
United Kingdom
A number of possible ways exist in which post grant amendment cane be effected
Section 27 – voluntary amendment;
Section 73 – amendment initiated by the comptroller to limit the claims to exclude the prior art; or
Section 75 amendment during patent infringement or revocation proceedings
The patent owner must give reasons for the amendment and if these involve distinguishing from defined prior art, the amendments will be examined to see whether they do.
Before an amendment under any of these proceedings is finalized, the proposed amendment is advertised on the Official Journal as being open to opposition.
In addition to the possibility of amending claims during invalidity proceedings, 
Article 126(1) provides that the patentee may file a request for a trial for correction of a patent, provided, however, that such correction shall be limited to the following:
(i) restriction of the scope of claims;
(ii) correction of errors; and
(iii) clarification of an ambiguous statements.
The list of permissible corrections in response to an invalidity trial is similar. Prior to the final decision in the invalidity trial, a preliminary opinion will be issued, in response to which a request for correction may be filed during the invalidity proceedings.
The courts may, but rarely do stay infringement actions pending the outcome of an invalidity trial.
Separation of amendment proceedings from court proceedings leads to the issues that arose in Fresnius and Virgin.  However, treating allowability of amendments simply as an issue for resolution between parties in a dispute can be prejudicial to third parties.  It may be time to look in more detail at the Australian way.

John Richards is Of Counsel and resident in the New York Office of Ladas & Parry and has more than four decades of patent experience. John specializes in chemical and biochemical patent matters including drafting and prosecution of patent applications in these fields in the United States, Europe and abroad. John handled the global patenting and licensing for the groundbreaking Alzheimer’s Disease drug known as Razadyne in the U.S and Reminyl internationally.

John can be contacted on  (212) 708-1915 or by email at

Related articles