We are currently developing a new site to host the Patent Manual of Practice and Procedure. The BETA version of this site is now available for you to review. The information and content displayed in the BETA site is only available for testing purposes. Do not use or reference the information in the BETA site when making any decisions or actions regarding IP rights. Types of Broad Claims

Date Published

Broad claims can be classified into four types:

Type I – Many claims in one application

Most patents typically have 10 to 20 claims, but sometimes applications are filed that have many hundreds, or even thousands, of claims. A large number of claims mean that the search and examination is inevitably compromised.

Type II – Many possibilities in one claim

Examples of this include Markush claims and some cases in the biotechnology field.  

Mainly used in chemistry, a Markush claim or structure is a claim with multiple functionally equivalent chemical entities allowed in one or more parts of the compound.

It is not possible to fully search these types of claims.  If the examiner concentrates on the worked examples or even generalized structures based upon the examples, large tracts of claimed matter will go unsearched.  These problems are only partially alleviated by electronic structure searching tools because in many cases the, the search engine will be unable to cope with the generality of the structure the examiner wishes to search.

Further information on Markush claims is provided in 1.1.19 Annex AA.

Type III – Desideratum claims

These are claims which set out a desired result without explaining in the claim how the result is achieved.  Such claims are often speculative and not commensurate with the contribution the inventor has made to the art.

Type IV – Some parametric claims

Where a parameter is used to define a product, it can be a problem comparing the product with the prior art either because the parameter used is unusual or unusual in the context of the characteristic being measured.  Occasionally an applicant will devise an entirely new parameter and use it to define the invention.  The product may be known but not described in the prior art in terms of the new parameter.  It makes comparisons with the prior art difficult.

Also a claim may define many parameters and/or large ranges for the parameters defined. Claims of this type are not unlike Markush claims in the large numbers of possibilities included in the scope of the claim.

It is not possible to properly search or examine claims of these four types, and with claims of types II to IV searching inevitably only covers a small proportion of the huge scope claimed.

See also Introduction, 1.1.19 Annex H, Search Considerations and Broad Claims.

Examples of search strategies for each of the claim types

Type I Claim:  Many claims in the one application

Example a) An application contains 480 claims, of which 38 are independent. There is no clear distinction between the independent claims because of overlapping scope. There are so many claims, and they are drafted in such a way that they are not in compliance with Article 6 and Rule 6. However, there is a reasonable basis in the description, for example from a particular passage, that clearly indicates which subject matter might be expected to be claimed.

The search should be based on the subject matter that would be expected to be claimed. In the written opinion, the claims should be objected to on the non-prior art grounds of lack of compliance with Article 6 and Rule 6. The International Searching Authority should also include in the objection on non-compliance with Article 6 and Rule 6 an indication to what degree these objections have been taken into account for the purposes of determining the extent of the search, and this extent should be indicated as precisely as possible, for example by a brief written description of the searched subject matter, where possible citing a particular passage.

Example b) An application contains 160 claims, of which 10 claims are independent.

The scope of various independent claims is clear and they can be grouped into 4 separate inventions.

  1. Compounds of formula Ia or pharmaceutically acceptable derivative thereof, pharmaceutical compositions comprising these compounds, methods of treating or preventing disorders characterised by impaired protein trafficking comprising the administration of these compounds and method of producing a protein comprising culturing a cell in the presence of these compounds.
  2. Compounds of formula IIa or pharmaceutically acceptable derivative thereof, pharmaceutical compositions comprising these compounds, methods of treating or preventing disorders characterised by impaired protein trafficking comprising the administration of these compounds and method of producing a protein comprising culturing a cell in the presence of these compounds.
  3. A method of treating or preventing disorders characterised by impaired protein trafficking comprising the administration of doxorubicin, cycloheximide, hygromycin, novobiocin, aureobasidin or tunicamycin.
  4. Methods of identifying compounds that rescue or increase impaired endoplasmic reticulum-mediated transport, enhance protein secretion, rescue impaired protein trafficking, rescue impaired Rab-mediated protein trafficking, inhibit the expression of protein defined therein or inhibit the activity of proteins defined therein.

Search Strategy

A unity objection is taken, and the search based on the invention(s) for which fees have been paid. If no additional fees are paid, the first invention should be searched.

A search of the inventive concept is carried out by performing a structure search for formula Ia, and combining the search results with keywords like protein trafficking, endoplasmic reticulum, lysosomal storage disorder, Huntington’s disease, Ta-Sachs, Hypercholesterolemia, cystic-fibrosis, diabetes etc. If this search provides no citations, results of the broader search for the compounds of formula Ia per se should be considered.

Type II claim:  Many Possibilities

Example a) Markush Claims

Claim 1:

Compounds of Formula (VII), defined as follows:


The variables in the formula are defined such that a conservative estimate of the number of compounds falling within the scope of this Markush claim was calculated as approximately 27 x 1025.  However, the description contains only six examples of compounds of formula (VII).  A search covering the entire scope of claim 1 produces hundreds of citations (too many to cite).  

Search Strategy:

The initial search should focus on the six exemplary compounds of formula (VII) disclosed in the description.  If any of these example compounds are disclosed in the prior art, then the strongest argument for lack of novelty of the claim will be based on the citations pertaining to these compounds, since they comprise the core of the alleged invention.  The broader aspect of the search should attempt to cover the entire scope of the Markush claim.  In the event that this produces such a large number of citations that it is not practicable to cite them all, the examiner should exercise professional judgement in selecting citations upon which to base novelty objections, with a view to restricting the scope of the claimed subject matter as much as possible, whilst placing the applicant on notice (in Box VIII as described below) that the list of citations provided is not an exhaustive one.

In the event that it is not possible to search the entire scope of the Markush claim (due to technical constraints associated with substructure searching), the broader aspect of the search should at least attempt to cover all the general compound classes represented by the examples.

Example b) Reach through claims

Claim 1

An isolated TKO receptor.

Claim 2

An isolated compound which modulates the expression or activity of the TKO receptor.


Claim 1 is directed to a receptor the inventors have identified and isolated and ascribed a function to. Claim 2 is a reach through claim, so called because it is attempting to reach through and claim future developments such as drugs which modulate the receptor. It might be the receptor is involved in pain perception or associated with a particular disease and the potential market for the drugs is speculated as being quite lucrative. Claim 2 is also very broad as it is not just limited to anything which interacts with the receptor or its gene but also includes compounds that interact with something else to trigger a cascade of events causing the activity or expression of the receptor to be modulated.

Search Strategy

The search should be limited to the activity of the compound and a comment made about full description under Article 5 (see below).  On some occasions the specification will give a list of known compounds which will modulate the activity or expression of the receptor, which become the citations.  No broader search is possible in this case, and this should be indicated at Box VIII.

Type III claim:  Desideratum.

Example a)

Claim 1:

An optical fibre adapted in a manner such that it guides an optical signal substantially only in one non-degenerate mode, wherein an electro-magnetic field carrying the optical signal is symmetric with respect to rotation about the fibre axis.


This claim defines a solution to a well known problem in the art – to have an optical fibre that guides an optical signal substantially only in one non-degenerate mode. The existing optical fibres all have a common disadvantage – they guide light substantially in one degenerate mode.

Search Strategy:

Claim 1 is speculative in nature as it defines the desired result without explaining how the result is achieved. However, it is not unusual that a speculatively claimed result may be genuinely novel and inventive, and the ‘claiming by result’ is an attempt to acquire the broadest possible monopoly in a potentially important new field.

The search strategy should be designed to include multiple ‘sub-strategies’ in order to address drafting deficiencies related to the speculative nature of claim 1. The key objective should be to retrieve the closest prior art to the inventive concept focusing on the disclosed embodiments. Multiple sub-strategies should cover different technical aspects of how the relevant possible modes for light propagation in optical fibres can be described:

  • the technical names of modes (single-mode, non-degenerate mode, TE01, TEM01, etc.);
  • the spatial/geometric characteristics of the corresponding electro-magnetic field (symmetric, annular, ring, etc.);
  • the relevant physical parameters of the optical fibre (refractive index, materials for core/cladding, structure of  core/cladding,  etc.).

If many highly relevant documents are found (indicating that the right technical area has been comprehensively covered), however, none of them discloses the features of claim 1, and the examiner is confident that, in light of the prior art retrieved, claim 1 is most likely to be novel and inventive, then no additional search effort is required. The speculative nature of claim 1 should be then addressed in the Written Opinion using Articles 5 and/or 6.

It should be noted that, when dealing with speculative claims in general, the examiner should also exercise professional judgement in assessing whether a different (broader) interpretation of the defined features is possible (this is not the case in the above example as all features of claim 1 have a well defined meaning in the art).

Example b)

Claim 1:

A cloned non-human mammal.

Claim 2:

A method of cloning a non-human mammal comprising:

i. fusing a non-human mammalian differentiated cell with an unactivated, enucleated metaphase II arrested oocyte to reconstruct an embryo;

ii. maintaining the reconstructed embryo without activation for sufficient time to reprogram the nucleus;

iii. activating the reconstructed embryo;

iv. transferring said reconstructed embryo to a non-human host mammal such that the reconstructed embryo develops to term.

Claim 1 is directed to a desired result without defining how the result is achieved. It is claiming the result of a cloned non-human mammal when achieved by any possible method. Such claims may be speculative, particularly when it is a result desirable in the art that others have been attempting to achieve. The contribution the invention makes to the art usually lies in the method by which the result is achieved, claim 2, rather than the result itself.

Search Strategy

The initial search strategy should focus on the methods by which the result is achieved. If any relevant citations are found against the methods, the result will also be rendered not novel. If no relevant citations are found, the search should be extended to methods of achieving the result known to the 3 person team or another technical expert, or to the result itself.

Example c)

Claim 1

An isolated protein that catalyzes the biosynthesis of piperitol and/or sesamin.

Claim 2

The protein of claim 1 comprising the amino acid sequence of SEQ ID NO: 3.


Biosynthesis of chemical compounds can involve a number of steps between a precursor compound and the final compound with different enzymes catalysing the various steps. Claim 1 includes any enzyme in the sesamin biosynthetic pathway, and given its broadest possible scope could include enzymes involved in the biosynthesis of the precursor for the seasmin biosynthetic pathway.  What the inventors have identified and isolated is the final enzyme in the pathway which has SEQ ID NO: 3, and which catalyses two reactions: the conversion of pinoresinol to piperitol and the conversion of piperitol to sesamin.

Search Strategy

The initial search would focus on the specific enzyme. As there is a sequence a sequence search would be performed, but a keyword search could also be performed to determine if the enzyme had previously been isolated but not sequenced. If nothing was found an expanded search would focus on the whole biosynthetic pathway.

Example d)

Claim 1

An air intake for a vehicle being constructed of at least two pieces of metallic material, each of which is formed so as to have a pair of matching edge shapes, the two pieces having such a shape as to define an air passageway there between when joined along their matching edges.


The claim in its broadest form defines a piece of metallic pipe (made of two pieces) or two pipes joined together providing the desired result of defining an air passageway.

However the invention as described is directed to an air intake made of top and bottom metallic parts where their edges are fused, the intake having specific shape, so it can be fitted over the car’s radiator.  

Search Strategy:

Claim 1 is speculative in nature as it is unduly wide.

In cases of broad claims as above it can be expected that prior art could be found quickly that undermines the novelty of the claim, therefore the search for the inventive concept should concentrate on the preferred embodiment (within the scope of the claim) including specific shape of the air intake (ie. the subject matter that the claims might reasonably be directed after they have been amended [PCT/GL/ISPE/7 at para 15.21]).  If citations are not found, the search strategy could be designed to quickly locate a document undermining the novelty of the claim by consulting internet web pages of Espace, USPTO or Google Patent Search (the search should not be restricted to specific examples).

Type IV claim:  Parametric.

Example a)

Claim 1

A solid detergent composition comprising from 8 to 60 wt % of a surfactant system and having a Grand Compatibility Index of at least 0.5.


The Grand Compatibility Index parameter is unknown in the prior art.  It turns out to be a function of a large number of other parameters, many of which are not quoted in the prior art.  Several pages of the application are taken up with an explanation of an elaborate testing procedure, using highly specialised laboratory equipment, which will, when followed, compute the grand compatibility Index of a given detergent.  There are five worked examples of detergent compositions satisfying the parameter in the description.

Search Strategy:

Since it is impossible to search the Grand Compatibility Index parameter as it is unknown in the prior art, the initial search should focus on the disclosed example compositions.  If any of the example compositions are disclosed in the prior art, it can be argued that these would inherently possess the feature of the Grand Compatibility Index parameter.  In the absence of any prior art pertaining to the examples themselves, the broader aspect of the search should attempt to cover anything that would prima facie possess the feature of the Grand Compatibility Index parameter, such as a search of compounds falling within the same class as those of the examples.  To illustrate; if the examples contain compounds that are aryl sulphonates and tetra-alkyl ammonium salts, then the search should at least cover these compound classes in an attempt to uncover compositions that at least satisfy the other identifiable limitations imposed by the claim (such as comprising from 8 to 60 wt % of the composition).  In an effort to render the claim more readily searchable, an objection may also be raised under Article 5 of the PCT, as discussed below.

Example b)

Claim 1

An interferometer for writing Bragg gratings comprising:

  • means for splitting a light beam into two coherent beams, and

  • an optical circuit for bringing the coherent beams to interference for writing the Bragg grating in a photosensitive material through induced refractive index changes in the material,

wherein an angle between the coherent beams after the means for splitting is less than 10o.


All features of claim 1, except for an angle being less than 10o, represent routine technical arrangements in the art. All existing interferometers for writing Bragg gratings include means for splitting a light beam into coherent beams and means for bringing the coherent beams to interference. There is always some angle between the coherent beams after splitting, but its value is not usually specified in technical disclosures in the art (at least, not in the abstract), though the drawings may provide a qualitative indication on how small or large the angle is.

Search Strategy:

Since it is highly unlikely that a specific value of the angle will be disclosed in any abstract of prior art documents, a broad search strategy should be adopted with a set of standard keywords in the field of writing Bragg gratings [like (grating)(s)(write, fabricate, produce, form, manufacture); interfere; etc.], followed with angle, split in an attempt to retrieve abstracts where the angle/splitting is mentioned. Then the most relevant documents should be identified by viewing a drawing included in every abstract (almost always in this technical field) and selecting those where the angle between the coherent beams appears to be small, or variable, or somewhat important to the invention. For the documents selected in this way, there will be a reasonable probability that an exact value of the angle will be disclosed somewhere in the full specification, so the examiner will be able to perform the novelty/inventive step determination for claim 1 objectively.

Example c)

Claim 1

An electrohydrodynamic device for generating an aerosol, said device incorporating a composition for creating an aerosol, said composition comprising:

a. a pharmaceutically active ingredient; and

b. a carrier material in which said pharmaceutically active ingredient is dissolved, emulsified, or suspended,

said pharmaceutically active ingredient and said carrier material being selected such that the composition has a predetermined range of properties comprising a surface tension of about 10 to 72 milliNewtons/meter, an electrical resistivity of about 10 to 100,000 ohm-meters, and an relative permittivity of about 5 to 500.


Electrohydrodynamic aerosol generators are well in known in the art of pharmaceutical inhalers. Electrohydrodynamic generators require the carrier to be liquid. Water has a surface tension of 72 mN/metre and there are few (if any) liquids with a surface tension less than 10 mN/metre. The relative permittivities (dielectric constant) of some liquids typically used as pharmaceutical carriers are: ethanol 24.3; glycol 42.2; water 80.4 and glycerol 42.5. Materials at the low end of the range claimed are typically solids (rubber 7) and materials at the high end are also typically solids (strontium titanate 310). Therefore liquids with relative permittivities of 5 and 500 as claimed can be considered to be rare. Also the claimed range of resistivity encompasses a very wide range of materials. Therefore the claim effectively includes all possible carrier materials.

Search Strategy:

Since it is impossible to search all possible pharmaceutical carrier materials, the initial search should focus on the disclosed example compositions and further restricted to the context of inhalers.

Ethanol is present as a major component in all of the exemplified compositions, therefore the initial search should focus on electrohydrodynamic inhalers using ethanol as the carrier.  If no citations result, the broader search would focus on electrohydrodynamic inhalers in general.

Back to top