As further evidence that the United States Patent and Trademark Office (Office) hates the chemical/pharma/biotech arts, the Office is proposing to revise the rules of practice pertaining to any claim using alternative language to claim one or more species. That is, if the claims use Markush or other forms of alternative language. This is all part of the Master 21st Century Strategic Plan where the PTO is trying desperately to reduce its workload by any means necessary. According to the USPTO, the search and examination of such claims consume a disproportionate amount of Office resources as compared to other types of claims.

In Ex parte Markush, 1925 Dec. Comm’r Pat. 126, 128 (1924), the Office officially sanctioned a claim drafting technique, already in use for some time, wherein the phrase ‘‘selected from the group consisting of’’ is followed by a closed listing of specific members of the group. Claims including such language became known as ‘‘Markush claims.’’ For example, if a claim to a chemical composition requires a particular alcohol, that alcohol could be defined via Markush language such as ‘‘an alcohol selected from the group consisting of methanol, ethanol, and isopropanol;’’ or ‘‘an alcohol of the formula R-OH, wherein R is selected from the group consisting of CH3-, CH3CH2-, and (CH3)2CH-.’’

In addition to the indefiniteness issue, another factor giving rise to claims using Markush language was the change from claims based on the central type of definition to those based on the peripheral definition. With the peripheral- type claims came the necessity of avoiding invalidity by reason of inoperative species which might be included within the metes and bounds of the claim. In mechanical cases, this problem is overcome by the use of elements defined as ‘‘means’’ but chemical claims do not lend themselves well to such a solution due to the fact that equivalence in chemical cases is difficult to establish. The Markush claim may be regarded as a partial solution to this problem, since it permits an applicant to claim a subgeneric group containing those materials which have been actually tested and known by applicant to be operable.

Most of the court decisions concerning claims that recite alternatives involve Markush practice and reflect problems associated with claiming compounds by their chemical structure. Current Office practice is that compounds that are defined by Markush language are directed to a single invention (i.e., have ‘‘unity of invention’’) when they ‘‘(1) share a common utility, and (2) share a substantial structural feature essential to that utility.’’

Current Office policy requires examination of all species of a claim that recites a Markush group when the alternatives are sufficiently few in number or so closely related that search and examination can be made without serious burden. That is, the Office cannot refuse to examine what applicants regard as their invention unless the subject matter in a claim lacks unity of invention.

In such case, however, the examiner may require applicant to elect a single species under 37 CFR 1.146 for initial search and examination to facilitate examination on the merits. If the elected species is not allowable, examination of the Markush claim will be limited to the elected species and any species not patentably distinct therefrom, and any separate claims to the elected species and any species not patentably distinct therefrom. Claims drawn to species patentably distinct from the elected species are held withdrawn from further consideration. If the elected species is allowable, then the search and examination of the Markush claim will be extended to non-elected species to the extent necessary to determine patentability of the claim. This may require a separate search and examination of each alternative.

The proposed rules are intended to provide a mechanism by which the Office can require a single claim to be limited to a single invention.

1. Each claim must be limited to a single invention.

A claim that is directed to multiple independent and distinct inventions would meet the statutory eligibility requirement for restriction set forth in 35 U.S.C. 121:

If two or more independent and distinct inventions are claimed in one application, the Director may require the application to be restricted to one of the inventions.

Through the use of the word ‘‘may,’’ the statute is permissive, not mandatory, and gives the Director discretion to require restriction.

In addition to proposing a requirement limiting a claim to a single invention, the Office is proposing to specify that when subject matter that reads on multiple species is defined in a single claim using alternative language, the claim is limited to a single invention when at least one of the following two conditions is met: (1) All of the species encompassed by the claim share a substantial feature essential for a common utility, or (2) all of the species are prima facie obvious over each other.

The Office proposes to encourage applicants, when filing a claim that employs alternative language, to provide an explanation as to why the claim is directed to a single invention. (WARNING: Prosecution Estoppel Ahead!)

The Notice claims that when an applicant submits an explanation in a timely manner, the examiner will fully consider it (and then summarily reject it).

The Office also proposes that if an application seeks the benefit under title 35, United States Code, of a prior-filed application and discloses subject matter that was not disclosed in the prior-filed application (a continuation-in-part), the applicant must identify which claim or claims in the application are disclosed in the manner provided by the first paragraph of 35 U.S.C. 112 in the prior-filed application.

2. Claims with alternatives will require a new format.

The Office proposes to require a simplified format for the presentation of such claims and to set forth conditions that must be met by any claim that uses alternative language by adopting language similar to that in the PCT Guidelines, specifically requiring that the number and presentation of alternatives in the claim not make the claim difficult to construe, and requiring that each alternative within a list of alternatives must be substitutable one for another. In addition, to reduce the complexity of determining whether a claim is directed to a single invention, the Office proposes to specify that no alternative may itself be defined as a set of further alternatives.

Finally, the Office proposes to specify that no alternative may be encompassed by any other alternative within a list of alternatives, unless there is no other practical way to define the invention. When alternatives partially overlap in scope, it is more difficult to determine whether a single claim encompasses more than one invention. Thus, a single claim that includes alternatives that either fully overlap (e.g., ‘‘selected from the group consisting of an adhesive agent, tape, and glue’’) or partially overlap (e.g., ‘‘selected from the group consisting of citrus fruits and tropical fruits’’) in scope may be subject to an objection.

The Office states that Applicants should file a series of individual claims from the broadest scope that they feel they are entitled to the narrowest scope they are willing to accept. Put differently, applicant should narrow the scope of protection sought via separate claims and not via nested sets of overlapping alternatives.

Couple this with the proposed rules on claim limits (see Changes to Practice for the Examination of Claims in Patent Applications, 71 Fed. Reg. 61) and this adds up to a skyrocketing increase in costs.

If you want to (try to) make your voice heard, written comments must be received on or before October 9, 2007. No public hearing will be held. Comments should be sent to

Comments may also be submitted by mail addressed to: Mail Stop Comments—Patents, Commissioner for Patents, P.O. Box 1450, Alexandria, VA, 22313–1450, or by facsimile to (571) 273–7754, marked to the attention of Kathleen Kahler Fonda, Legal Advisor, Office of the Deputy Commissioner for Patent Examination Policy.

In addition to comments on the proposed rules, the Office welcomes further suggestions for changes that would improve the examination of claims that recite Markush or other alternative language while appropriately balancing the interests of the Office with those of applicants and the public.

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  1. […] USPTO proposed new rules in the Federal Register that will allow an examiner to split one Markush claim into lots and lots […]

  2. pls tell me abt the type of claim mentioned herewith: A method of alleviating withdrawal symptoms of dependency or addiction to a substance selected from the group consisting of alcohol, amphetamines and morphine in a human being comprising administering to said human being in need thereof a Ginkgo biloba extract in an amount sufficient to alleviate said withdrawal symptoms, wherein said Ginkgo biloba extract comprises 20 to 30% of flavoneglycosides, 2.5 to 4.5% of ginkgolides A, B, C and J, 2 to 4% of bilobalide, less than 10% of proanthocyanidines and less than 10 ppm of compounds of alkylphenol type.

  3. […] also:  USPTO to Limit Markush (Alternative) Claims: Serious Cost Increase in the Forecast Posted March 11th, 2008 by Stephen Albainy-Jenei in Patent Reform, USPTO | […]

  4. There is no point in limiting markush claims, as they are the important means of coverage.

  5. […] USPTO to Limit Markush (Alternative) Claims: Serious Cost Increase in the Forecast Posted April 30th, 2008 by Stephen Albainy-Jenei in Patent Reform, USPTO | | […]