Third Party Observations explained

Third Party Observations (TPOs) provide a mechanism for third parties to file objections and evidence against a pending patent application which, if successful, can result in limitation or refusal of the patent application. Compared to post grant proceedings such as oppositions and revocation actions, TPOs are low-cost and can provide a highly effective tool in clearing the way for your product.

Who can file TPOs?

Focussing in on the situation in the UK and in other EPC states, any person can file TPOs at the EPO or the UKIPO in relation to ongoing patent proceedings. However, that person cannot already be a party to the proceedings. In other words, an applicant cannot file TPOs in relation to the proceedings for their own application.

TPOs can be filed anonymously, if wanted. In other words, a party can choose to file TPOs without identifying themselves. This may be advantageous if a party does not want the patent applicant to find out who is behind the TPOs.

When can TPOs be filed?

TPOs can be filed following the publication of a patent application and up until grant of the application. Any TPOs filed during this period must be considered by the Examiner and so can influence the examination procedure. In some cases, it is even possible to cause examination to be re-opened after the Examiner has decided to allow an application, if the TPOs are received before the date of grant and if they contain objections that prejudice grant of the application.

TPOs received after the decision to grant a patent application are deemed late and will not be considered by the Examiner, although they may be made available to the public on the register.

Additionally, at the EPO it is possible to file TPOs against a granted patent during opposition and appeal proceedings. So, if TPOs are filed after the grant of a patent and an opposition is subsequently filed against the patent, the TPOs will be considered as part of the opposition proceedings.

What can be included in TPOs?

TPOs can include objections relating to the ‘patentability’ of the invention. This means that the following grounds can be relied on in TPOs:

  • the claimed invention is not patentable (either because the subject matter is excluded from patentability or because it lacks novelty or inventive step):
  • the specification of the patent does not disclose the invention sufficiently clearly and completely for it to be carried out by a person skilled in the art ("insufficiency"):
  • a previous amendment extends beyond the content of the application as originally filed ("added subject matter"):
  • the claims are unclear:
  • the claims define multiple inventions (“lack of unity”).

The ability to raise lack of clarity and lack of unity objections in TPOs against a pending patent application is noteworthy, as it is not possible to attack a granted patent on these grounds during an EPO opposition.

In addition to arguments setting out the objections, TPOs can include evidence for supporting the objections. Evidence may typically be in the form of prior art documents, or documents which are used to substantiate an allegation of prior use.

How are TPOs filed?

TPOs should be filed in writing, either electronically, by mail, or hand delivered at the relevant patent office. At the EPO, TPOs must be filed in an official language (English, French or German). However, accompanying evidence may be filed in another language.

There is no official fee associated with the filing of TPOs.

What happens after TPOs are filed?

After TPOs are filed, the patent office will communicate the TPOs to the applicant or proprietor without delay, so that they can comment on them.

If the TPOs call into question patentability of the invention, then the TPOs must be considered by the Examiner during examination of the application. At the EPO, the Examiner will make every effort to issue the next office action on the patent application in question within three months of receipt of TPOs. However, this ‘acceleration’ of the proceedings does not occur if the TPOs are filed anonymously.

This information is simplified and must not be taken as a definitive statement of the law or practice.