Key Takeaways

  • Patent revocation is the legal cancellation of a granted patent, usually because it should not have been granted in the first place.
  • Grounds include lack of novelty, lack of inventive step, insufficient disclosure, wrongful ownership, or fraud.
  • In Europe, opposition must be filed within nine months, but revocation proceedings can follow even after this period.
  • Courts can revoke patents directly if legal grounds are met, and appeals can be taken to higher patent courts.
  • Revocation has significant consequences for damages, enforcement, and future patent strategies.
  • Both patentees and challengers need strong legal strategy and evidence, often involving expert attorneys.

Can a patent be revoked? A patent can be revoked if an aggrieved party files patent opposition or revocation proceedings to disprove the claims of the person who was granted the patent of their right of exclusivity.

What Are the Grounds for Patent Revocation in New Zealand?

If a party holds the view that a patentee should not be granted a patent or seeks the revocation of a granted patent, then the person can file a patent opposition or revocation proceedings based on the following reasons:

  • The patent's claims fail to spell out the subject matter which qualifies for a patent
  • The claim is not new or lacks inventive steps
  • The patent applicant is not the rightful owner of the invention
  • The details of the patent application fall short of specific requirements
  • The patent applicant has tried to secure the patent through false claims, fraud, or misrepresentation of facts.
  • The invention has been used in New Zealand secretly before the priority date
  • Granting the patent will be unlawful.

Common Global Grounds for Patent Revocation

While each jurisdiction has its own rules, most countries share common reasons for patent revocation:

  • Lack of novelty – The invention was already disclosed publicly before the patent was filed.
  • Lack of inventive step (obviousness) – The claimed invention would be obvious to a skilled professional.
  • Insufficient disclosure – The patent does not adequately explain how the invention works.
  • Wrongful ownership – The applicant was not the rightful inventor or assignee.
  • Fraud or misrepresentation – False or misleading statements were made during the patent application.
  • Non-patentable subject matter – The subject matter falls outside what is eligible for patents (e.g., abstract ideas, natural discoveries).
  • Failure to comply with procedural requirements – Non-payment of fees, late filings, or other administrative lapses.

These grounds highlight that patent revocation is not only about technical details but also legal compliance and ownership rights.

What Is the Requirement to File a Patent Revocation in Europe?

Regarding European or German patents, anybody can file an opposition for the revocation of a patent provided the opposition was filed within the nine-month period from the time when the grant of the patent was announced in the Patent Bulletin. In situations where the time for filing opposition proceedings has elapsed, or the opposition proceeding failed, the opposing party can still file a revocation proceeding against the granted patent.

Steps to Patent Revocation in Europe

The following are steps involved in patent revocation in Europe:

  • The opposition or revocation action must provide reasons it was wrong to grant the patent.
  • An experienced patent attorney should evaluate the success rate of the opposition or revocation action before it is filed by reviewing the file and relevant cases.
  • The company may file proceedings against the patent if the chances of success are considered to be high and the company can foot the bill.
  • When an opposition is filed, the Patent Office will reassess the relevant requirements for a grant or maintenance of the patent to determine their authenticity. A panel made up of the Patent Office officials will conduct the assessment.
  • Once the opposition has been examined, the Patent Office shall issue its decision on whether the patent should be revoked, maintain in limited form, or maintained as originally granted.
  • If the opposing party is not satisfied with the outcome of the proceedings, it may appeal the decision before the German Federal Patent Court.

Patent Revocation Proceedings in India

In India, patent revocation can be sought under Section 64 of the Patents Act. A petition can be filed before the Intellectual Property Appellate Board (IPAB), the High Court, or the Controller of Patents, depending on the circumstances.

Grounds include:

  • The invention was already publicly known or used in India.
  • The patent was obtained wrongfully or fraudulently.
  • The invention is not useful or is contrary to public order or morality.
  • The patent specification does not sufficiently describe the invention.

India also permits revocation on public interest grounds, for example, if the patented invention is not being worked in India and is needed for public health. This makes India’s system unique in balancing private rights with broader social welfare.

When Can the Court Revoke a Patent?

If the Federal Patent Court considers the revocation action to be justified, it may decide to revoke the patent.

Administrative vs. Judicial Revocation

Patent revocation can occur through administrative processes (before patent offices) or judicial processes (before courts).

  • Administrative revocation typically happens through opposition procedures. For example, in Europe, oppositions are reviewed by patent office panels within strict timelines.
  • Judicial revocation involves litigation, often where revocation is sought as a defense to infringement. Courts may revoke a patent entirely if the challenger proves invalidity on any accepted ground.

This dual-track system ensures both administrative oversight and judicial review, providing multiple layers of accountability.

Where Can Appeals to Revocation Be Filed?

The German Federal Supreme Court is responsible for hearing appeals against the decision of revocation boards.

Consequences of Patent Revocation

Revocation has far-reaching consequences for both patentees and third parties:

  • Loss of exclusivity – Once revoked, the invention enters the public domain and can be freely used.
  • Impact on licensing agreements – Contracts based on a revoked patent may be unenforceable.
  • Financial implications – Companies may lose revenue streams tied to royalties.
  • Effect on ongoing litigation – Revocation can nullify infringement cases, making them moot.
  • Market consequences – Competitors may enter the market quickly after a revocation, changing competitive dynamics.

Because of these effects, both patent owners and challengers must carefully weigh the risks and benefits before pursuing or defending revocation.

What Is Provided Under Case Law of the Boards of Appeal Sec. 4.5.2?

Under G 9/92 and G 4/93 (OJ 1994, 875), during opposition appeal proceedings, the amount of amendments which the patent holder can do depends on the outcome of the original opposition proceedings and on whether the patentee filed an admissible appeal or he was merely responding to the opposition proceedings.

Can a Patentee Still Pursue Damages If Parts of the Patent Have Been Invalidated?

Patentees can no longer claim damages in English courts if certain parts of the patent have been invalidated after the case has been decided in favor of their claim on infringement. This judgment has halted a century's precedence that allows patentees to seek damages even after the patent has been revoked.

The Supreme Court has also considered the possibility of allowing defendants to pursue revocation of damages after it has been awarded in such situations, even after the damages have been paid.

Strategies to Defend Against Revocation

Patent holders often employ several strategies to defend against revocation:

  • Amending claims – Narrowing or clarifying claims to avoid invalidity.
  • Proving inventive step with expert testimony – Demonstrating that the invention was not obvious at the time of filing.
  • Challenging prior art evidence – Showing that cited prior art is irrelevant or insufficient.
  • Arguing procedural defects – Asserting that the challenger failed to follow procedural rules.

These defenses emphasize the importance of robust initial drafting and continuous monitoring of competitors’ challenges.

When Can the Defendant Rely on the Revocation as to Damages?

The Supreme Court recommends changing the way the Patent Court handles applications to stay proceedings until an EPO opposition is filed.

The Supreme Court holds a clear position in circumstances where an English court decides that a patent is valid and infringed, regardless of whether it's English or European, after which the patent was revoked or amended retrospectively. The defendant is allowed to rely on the revocation or amendment of the patent with regards to damages. Based on the speech of Lord Neuberger, the chances of an inquiry taking place are very slim in such situations.

Frequently Asked Questions

  1. What is the difference between patent opposition and revocation?
    Opposition is usually filed soon after grant, while revocation can be pursued later in court or before a patent authority.
  2. Can a revoked patent be reinstated?
    No. Once revoked, the rights are permanently lost, and the invention enters the public domain.
  3. Who can file for patent revocation?
    In most jurisdictions, any interested party can file, including competitors or even public interest groups.
  4. How long does patent revocation take?
    It varies by jurisdiction—administrative opposition may take months to a few years, while court revocation can take longer.
  5. What should patentees do to reduce revocation risks?
    Ensure strong drafting, pay fees on time, disclose fully, and conduct prior art searches before filing.

If you need more information about patent revocation, you can post your legal need on UpCounsel's marketplace. UpCounsel accepts only the top 5 percent of lawyers to its site. Lawyers on UpCounsel come from law schools such as Harvard Law and Yale Law and average 14 years of legal experience, including work with or on behalf of companies like Google, Menlo Ventures, and Airbnb.