Under what condition can a terminal disclaimer be filed?

A terminal disclaimer can be filed when the claims of a second patent are found to be non-patentably distinct from the claims of a first patent, or when the second patent is deemed to be too similar to the first patent. The purpose of a terminal disclaimer is to overcome rejection based on double patenting, which arises when two patents share the same inventive idea or subject matter.

Filing a terminal disclaimer typically requires that both patents are owned by the same entity. This is because the terminal disclaimer effectively waives part of the patent term of the later patent in order to avoid issues of double patenting with respect to the earlier patent. The condition of having the same owner ensures that the assignee is agreeing to the limitation imposed by the terminal disclaimer, acknowledging that they can only enforce the later patent alongside the earlier one.

The other conditions mentioned do not align with the requirements for filing a terminal disclaimer. If patents are owned by different entities, the same entity requirement would not be met. Claims can conflict or not, but that does not change the ownership requirement for the disclaimer itself. Additionally, if the patents are for different inventions, there may not be a need for a terminal disclaimer to address double patenting, as that issue arises from similar inventions