An Update on Unity Objections, Elections, and Double Patenting Considerations During Canadian Examination

Canada has unique local law on double patenting. Like the U.S., there is an obviousness standard for double patenting, but, unlike the U.S., terminal disclaimer is not available. The Supreme Court of Canada has indicated that a determination of non-unity during examination can safeguard a subsequent divisional application from double patenting challenges.1 Recent, unpublished practice changes at the Canadian Intellectual Property Office (CIPO) mean that applicants must now be careful to avoid losing the ability to have this important determination made for newly added claims.

Historically, Canada’s double patenting quirks have been balanced by flexible examination practices that have allowed applicants to achieve a "forced" division in alignment with overall patenting aims and evolving commercial interests.

Some of this remains true. When a unity objection is raised during Canadian examination, applicants still have the option of electing a subject matter group or of requesting reconsideration of the objection (with or without claim amendments). The latter option is useful when the unity objection is premature, or when an applicant has claims of a different scope that it wishes to present for consideration.

The Patent Act2 sets out divisional practice in subsection 36(2):

Where an application (the "original application") describes and claims more than one invention, the applicant may limit the claims to one invention only, and any other invention disclosed may be made the subject of a divisional application, if the divisional application is filed before the issue of a patent on the original application.

Recent observed changes to examination practices following unity objections, however, mean that applicants must now exercise caution (1) to avoid being boxed in to subject matter that was not intended as an election, and (2) to maintain the ability to pursue divisional applications for other subject matter of interest without risk of double patenting.

The changes appear to have a basis in internal CIPO Examiners’ Bulletin No. 2017-P4-B3, which endorses a more restrictive approach than is apparent from the language of the Patent Act. The bulletin states that examiners must use standard wording to acknowledge elections:

When examining claims to elected subject-matter, where the application is not in a state to be approved for allowance, the examiner must include [standard wording paragraphs] in their report. This [standard wording] indicates that the applicant cannot "switch groups" (amend the claims to be directed to the non-elected subject-matter) during prosecution of the particular application.

The bulletin also states that there may be a so-called "implicit election" even when no election is acknowledged by an applicant:

An election is considered to have occurred when the applicant limits the claims to fewer inventions than were defined in the claims set containing the section 36 defect as identified by examiners in a previous report. An election may be apparent from an explicit statement in the response (e.g., In response to the section 36 defect identified by the examiner, the applicant elects Group A — claim 1-x), or it may be implicit and determined by the manner in which the claims were amended (e.g., certain claims have been deleted or modified, leaving only the claims corresponding to Group A or a set of claims which do not lack unity despite not conforming exactly to one of the groups of the original unity defect).

While some of these details are included in CIPO’s Manual of Patent Office Practice (MOPOP)4, there is no indication in MOPOP that a subject matter group other than the groups identified in unity objection could be deemed "implicitly elected". The text of the bulletin indicates that this could happen when the claims are amended after a unity objection, or when the number of perceived inventions is reduced in any way.

Once an election — explicit or implicit — has been acknowledged by an examiner, the bulletin indicates that claims may not be amended to include subject matter that is outside the scope of that election. If this occurs, the bulletin states that examination should be halted until the offending subject matter is removed:

Where the examiner has used this [standard wording], and the applicant subsequently amends the claims to be directed to non-elected subject-matter (i.e., the applicant switches groups), the applicant is considered to be non-compliant with subsection 36(2) of the Patent Act. The examiner must identify the unity defect in a report… and defer substantive examination on the non-elected subject matter until the unity defect is overcome.

It is the combination of an implicit election — the characterization of which is left entirely to the discretion of an examiner — and the inability to add subject matter beyond the election that is new, and that could be problematic for applicants.

In view of the impact of unity objections on double patenting, the ability to have unity reconsidered for a revised claim set has long been an important (and attractive) feature of Canadian examination. Applicants often become aware, through the events of foreign examination, that they are entitled to claims of a different scope. Now, an applicant could now find itself inadvertently limited in later examination by an earlier "implicit election" to which it did not consent, and which it did not intend to make. Subsequent amendments to broaden the claims or to add subject matter never before considered could bring examination to a standstill, and objections based on this new practice have been observed.

Broadening amendments will be particularly problematic if they overlap and extend beyond a previous implicit election. An applicant who wishes to pursue broader subject matter following such an implicit election may be required to file a divisional application, and to abandon the parent, to reset examination.

Ideally, a change with this sort of impact would be subject to public consultation and external publication. Unfortunately, there is no acknowledgement in the bulletin that the practice constitutes a change.

Certainty could be restored to this aspect of examination if CIPO were to revert to its previous practice, and avoid the subjective identification of restrictive elections other than those made by applicants. Until that happens, applicants should be explicit with CIPO whenever an election is not intended after a unity objection. Even so, when there are new claims of interest at the time of a unity objection, all claims should be presented together for reconsideration to avoid the risk of a limiting implicit election.

1 Consolboard Inc v Macmillan Bloedel (Saskatchewan) Ltd (1981) 56 CPR (2d) 145 (SCC) at p169.

2 R.S.C., 1985, c. P-4




Graeme Boocock PhD


Intellectual Property