Define: Marking Estoppel

Marking estoppel is a legal doctrine that prevents a patent owner from seeking damages for patent infringement if they fail to mark their patented product with the appropriate patent number.

Marking estoppel applies when a patented product is sold or offered for sale in the United States.

The purpose of marking estoppel is to provide notice to the public that a product is patented, allowing potential infringers to make informed decisions and avoid liability.

If a patent owner fails to mark their product, they may lose the right to seek damages for patent infringement. However, they can still pursue other remedies such as injunctive relief.

Yes, there are exceptions to marking estoppel. For example, if the patented product is not easily marked, such as a large machine, the patent owner may not be required to mark it.

To comply with marking estoppel, a patented product should be marked with the word “patent” or “pat.” followed by the patent number.

Yes, marking estoppel can be used against a patent owner in litigation as a defence to a claim for damages.

No, a patent owner cannot retroactively mark their product to avoid marking estoppel. The marking must be done at the time of sale or offer for sale.

Yes, a patent owner can still enforce their patent even if they fail to mark their product. They may be able to seek other remedies such as injunctive relief or reasonable royalties.

A potential infringer can determine if a product is patented by looking for the word “patent” or “pat.” followed by a patent number on the product or its packaging. They can also search the United States Patent and Trademark Office’s database for the patent number.