MPEP § 1850 — MPEP § 1850
Current through: 2022-07-01

1850-Unity of Invention Before the International Searching Authority 
 
 

 
 
 
 
 
 
 
 

 

 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 

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 Chapter 1800 

 Section 1850 
 

 
 
 
 
 
 1850 Unity of Invention Before the International Searching
 Authority [R-01.2024]
 

 
 PCT Rule 13 

 Unity of Invention 

 
 13.1 Requirement

 The international application shall relate to one invention only
 or to a group of inventions so linked as to form a single general inventive
 concept (“requirement of unity of invention”).
 

 

 
 13.2 Circumstances in Which the Requirement of Unity of
 Invention Is to Be Considered Fulfilled
 

 Where a group of inventions is claimed in one and the same
 international application, the requirement of unity of invention referred to in
 Rule
 13.1 shall be fulfilled only when there is a technical
 relationship among those inventions involving one or more of the same or
 corresponding special technical features. The expression “special technical
 features” shall mean those technical features that define a contribution which
 each of the claimed inventions, considered as a whole, makes over the prior
 art.
 

 

 
 13.3. Determination of Unity of Invention Not Affected by
 Manner of Claiming
 

 The determination whether a group of inventions is so linked as
 to form a single general inventive concept shall be made without regard to
 whether the inventions are claimed in separate claims or as alternatives within
 a single claim.
 

 

 
 13.4. Dependent Claims

 Subject to Rule 13.1 , it shall be
 permitted to include in the same international application a reasonable number
 of dependent claims, claiming specific forms of the invention claimed in an
 independent claim, even where the features of any dependent claim could be
 considered as constituting in themselves an invention. 
 

 

 
 13.5. Utility Models

 Any designated State in which the grant of a utility model is
 sought on the basis of an international application may, instead of
 Rules
 13.1 to 13.4 , apply in respect of
 the matters regulated in those Rules the provisions of its national law
 concerning utility models once the processing of the international application
 has started in that State, provided that the applicant shall be allowed at least
 two months from the expiration of the time limit applicable under
 Article
 22 to adapt his application to the requirements of the
 said provisions of the national law.
 

 

 

 
 PCT Rule 40 

 Lack of Unity of Invention (International
 Search) 

 
 40.1 Invitation to Pay Additional Fees; Time
 Limit
 

 The invitation to pay additional fees provided for in
 Article
 17(3)(a) shall: 
 

 
 (i) specify the reasons for which the international
 application is not considered as complying with the requirement of unity
 of invention;
 

 (ii) invite the applicant to pay the additional fees within
 one month from the date of the invitation, and indicate the amount of
 those fees to be paid; and
 

 (iii) invite the applicant to pay, where applicable, the
 protest fee referred to in Rule 40.2(e) within
 one month from the date of the invitation, and indicate the amount to be
 paid.
 

 
 

 

 
 40.2. Additional Fees

 
 (a) The amount of the additional fees due for searching
 under Article 17(3)(a) shall be determined by the
 competent International Searching Authority.
 

 (b) The additional fees due for searching under
 Article 17(3)(a) shall be payable direct to the
 International Searching Authority.
 

 (c) Any applicant may pay the additional fees under
 protest, that is, accompanied by a reasoned statement to the effect that
 the international application complies with the requirement of unity of
 invention or that the amount of the required additional fees is
 excessive. Such protest shall be examined by a review body constituted
 in the framework of the International Searching Authority, which, to the
 extent that it finds the protest justified, shall order the total or
 partial reimbursement to the applicant of the additional fees. On the
 request of the applicant, the text of both the protest and the decision
 thereon shall be notified to the designated Offices together with the
 international search report. The applicant shall submit any translation
 thereof with the furnishing of the translation of the international
 application required under Article 22 . 
 

 (d) The membership of the review body referred to in
 paragraph (c) may include, but shall not be limited to, the person who
 made the decision which is the subject of the protest.
 

 (e) The examination of a protest referred to in paragraph
 (c) may be subjected by the International Searching Authority to the
 payment to it, for its own benefit, of a protest fee. Where the
 applicant has not, within the time limit under Rule
 40.1(iii) , paid any required protest fee, the
 protest shall be considered not to have been made and the International
 Searching Authority shall so declare. The protest fee shall be refunded
 to the applicant where the review body referred to in paragraph (c)
 finds that the protest was entirely justified.
 

 
 

 

 

 
 37 CFR 1.475 Unity of invention before the International Searching Authority, the
 International Preliminary Examining Authority and during the national
 stage. 

 
 (a) An international and a national stage application shall
 relate to one invention only or to a group of inventions so linked as to
 form a single general inventive concept (“requirement of unity of
 invention”). Where a group of inventions is claimed in an application, the
 requirement of unity of invention shall be fulfilled only when there is a
 technical relationship among those inventions involving one or more of the
 same or corresponding special technical features. The expression “special
 technical features” shall mean those technical features that define a
 contribution which each of the claimed inventions, considered as a whole,
 makes over the prior art.
 

 (b) An international or a national stage application containing
 claims to different categories of invention will be considered to have unity
 of invention if the claims are drawn only to one of the following
 combinations of categories:
 
 (1) A product and a process specially adapted for the
 manufacture of said product; or
 

 (2) A product and a process of use of said product;
 or
 

 (3) A product, a process specially adapted for the
 manufacture of the said product, and a use of the said product;
 or
 

 (4) A process and an apparatus or means specifically
 designed for carrying out the said process; or
 

 (5) A product, a process specially adapted for the
 manufacture of the said product, and an apparatus or means
 specifically designed for carrying out the said process.
 

 
 

 (c) If an application contains claims to more or less than one
 of the combinations of categories of invention set forth in paragraph (b) of
 this section, unity of invention might not be present.
 

 (d) If multiple products, processes of manufacture or uses are
 claimed, the first invention of the category first mentioned in the claims
 of the application and the first recited invention of each of the other
 categories related thereto will be considered as the main invention in the
 claims, see PCT Article 17(3)(a) 
 and § 1.476(c) .
 

 (e) The determination whether a group of inventions is so linked
 as to form a single general inventive concept shall be made without regard
 to whether the inventions are claimed in separate claims or as alternatives
 within a single claim.
 

 
 
 I. THE REQUIREMENT FOR “UNITY OF INVENTION” Any international application must relate to one invention only or
 to a group of inventions so linked as to form a single general inventive concept
 ( PCT Article
 3(4)(iii) and 17(3)(a) , PCT Rule
 13.1 , and 37 CFR 1.475 ). Observance of
 this requirement is checked by the International Searching Authority and may be
 relevant in the national (or regional) phase.
 

 The decision in 
 Caterpillar Tractor Co. v. Commissioner of Patents and
 Trademarks, 650 F. Supp. 218, 231 USPQ 590 (E.D. Va. 1986) held that
 the Patent and Trademark Office interpretation of 37 CFR
 1.141(b)(2) as applied to unity of invention determinations
 in international applications was not in accordance with the Patent Cooperation
 Treaty and its implementing regulations. In the Caterpillar international
 application, the USPTO acting as an International Searching Authority, had held lack
 of unity of invention between a set of claims directed to a process for forming a
 sprocket and a set of claims drawn to an apparatus (die) for forging a sprocket. The
 court stated that it was an unreasonable interpretation to say that the expression
 “specifically designed” as found in former PCT Rule 13.2(ii) means that the process
 and apparatus have unity of invention if they can only be used with each other, as
 was set forth in MPEP § 806.05(e) . 
 

 Therefore, when the Office considers international applications as
 an International Searching Authority, as an International Preliminary Examining
 Authority, and during the national stage as a Designated or Elected Office under
 35 U.S.C.
 371 , PCT Rule 13.1 and
 13.2 will be followed when considering unity of invention of
 claims of different categories without regard to the practice in national
 applications filed under 35 U.S.C. 111 . No change was
 made in restriction practice in United States national applications filed under
 35 U.S.C.
 111 outside the PCT. 
 

 In applying PCT Rule 13.2 to international
 applications as an International Searching Authority, an International Preliminary
 Examining Authority and to national stage applications under 35 U.S.C.
 371 , examiners should consider for unity of invention all the
 claims to different categories of invention in the application and permit retention
 in the same application for searching and/or preliminary examination, claims to the
 categories which meet the requirements of PCT Rule 13.2 . 
 

 PCT Rule
 13.2 , as it was modified effective July 1, 1992, no longer
 specifies the combinations of categories of invention which are considered to have
 unity of invention. Those categories, which now appear as a part of Chapter 10 of
 the International Search and Preliminary Examination Guidelines, may be obtained
 from the Patent Examiner’s Toolkit link or from WIPO’s website ( www.wipo.int/pct/en/texts/gdlines.html ). The categories of
 invention in former PCT Rule 13.2 have been replaced with a statement describing the
 method for determining whether the requirement of unity of invention is satisfied.
 Unity of invention exists only when there is a technical relationship among the
 claimed inventions involving one or more special technical features. The term
 “special technical features” is defined as meaning those technical features that
 define a contribution which each of the inventions considered as a whole, makes over
 the prior art. The determination is made based on the contents of the claims as
 interpreted in light of the description and drawings. Chapter 10 of the
 International Search and Preliminary Examination Guidelines also contains examples
 concerning unity of invention.
 

 II. DETERMINATION OF “UNITY OF INVENTION” An international application should relate to only one invention
 or, if there is more than one invention, the inclusion of those inventions in one
 international application is only permitted if all inventions are so linked as to
 form a single general inventive concept ( PCT Rule 13.1 ). With respect to
 a group of inventions claimed in an international application, unity of invention
 exists only when there is a technical relationship among the claimed inventions
 involving one or more of the same or corresponding special technical features. The
 expression “special technical features” is defined in PCT Rule 13.2 
 as meaning those technical features that define a contribution which each of the
 inventions, considered as a whole, makes over the prior art. The determination is
 made on the contents of the claims as interpreted in light of the description and
 drawings (if any).
 

 Whether or not any particular technical feature makes a
 “contribution” over the prior art, and therefore constitutes a “special technical
 feature,” should be considered with respect to novelty and inventive step. For
 example, a document discovered in the international search shows that there is a
 presumption of lack of novelty or inventive step in a main claim, so that there may
 be no technical relationship left over the prior art among the claimed inventions
 involving one or more of the same or corresponding special technical features,
 leaving two or more dependent claims without a single general inventive concept.
 

 Lack of unity of invention may be directly evident “ a
 priori, ” i.e., before considering the claims in relation to any prior
 art, or may only become apparent “ a posteriori, ” i.e., after
 taking the prior art into consideration. For example, independent claims to A + X, A
 + Y, X + Y can be said to lack unity a priori as there is no
 subject matter common to all claims. In the case of independent claims to A + X and
 A + Y, unity of invention is present a priori as A is common to
 both claims. However, if it can be established that A is known, there is lack of
 unity a posteriori, since A (be it a single feature or a group of
 features) is not a technical feature that defines a contribution over the prior
 art.
 

 Although lack of unity of invention should certainly be raised in
 clear cases, it should neither be raised nor maintained on the basis of a narrow,
 literal or academic approach. There should be a broad, practical consideration of
 the degree of interdependence of the alternatives presented, in relation to the
 state of the art as revealed by the international search or, in accordance with
 PCT Article
 33(6) , by any additional document considered to be relevant.
 If the common matter of the independent claims is well known and the remaining
 subject matter of each claim differs from that of the others without there being any
 unifying novel inventive concept common to all, then clearly there is lack of unity
 of invention. If, on the other hand, there is a single general inventive concept
 that appears novel and involves inventive step, then there is unity of invention and
 an objection of lack of unity does not arise. For determining the action to be taken
 by the examiner between these two extremes, rigid rules cannot be given and each
 case should be considered on its merits, the benefit of any doubt being given to the
 applicant. 
 

 From the preceding paragraphs it is clear that the decision with
 respect to unity of invention rests with the International Searching Authority or
 the International Preliminary Examining Authority. However, the International
 Searching Authority or the International Preliminary Examining Authority should not
 raise objection of lack of unity of invention merely because the inventions claimed
 are classified in separate classification groups or merely for the purpose of
 restricting the international search to certain classification groups.
 

 Unity of invention has to be considered in the first place only in
 relation to the independent claims in an international application and not the
 dependent claims. By “dependent” claim is meant a claim which contains all the
 features of one or more other claims and contains a reference, preferably at the
 beginning, to the other claim or claims and then states the additional features
 claimed ( PCT Rule
 6.4 ). The examiner should bear in mind that a claim may also
 contain a reference to another claim even if it is not a dependent claim as defined
 in PCT Rule
 6.4 . One example of this is a claim referring to a claim of a
 different category (for example, “Apparatus for carrying out the process of Claim 1
 ...,” or “Process for the manufacture of the product of Claim 1 ...”). Similarly, a
 claim to one part referring to another cooperating part, for example, “plug for
 cooperation with the socket of Claim 1 ...”) is not a dependent claim. 
 

 If the independent claims avoid the prior art and satisfy the
 requirement of unity of invention, no problem of lack of unity arises in respect of
 any claims that depend on the independent claims. In particular, it does not matter
 if a dependent claim itself contains a further invention. For example, suppose claim
 1 claims a turbine rotor blade shaped in a specified manner such that it avoids the
 prior art, while claim 2 is for a “turbine rotor blade as claimed in claim 1” and
 produced from alloy Z. Then no objection under PCT Rule 13 arises either
 because alloy Z was new and its composition was not obvious and thus the alloy
 itself already contains the essential features of an independent possibly later
 patentable invention, or because, although alloy Z was not new, its application in
 respect of turbine rotor blades was not obvious, and thus represents an independent
 invention in conjunction with turbine rotor blades. As another example, suppose that
 the main claim defines a process avoiding the prior art for the preparation of a
 product A starting from a product B and the second claim reads: “Process according
 to claim 1 characterized by producing B by a reaction using the product C.” In this
 case, too, no objection arises under PCT Rule 13 , whether or not the
 process for preparation of B from C is novel and inventive, since claim 2 contains
 all the features of claim 1. Equally, no problem arises in the case of a
 genus/species situation where the genus claim avoids the prior art, provided the
 genus claim is directed only to alternatives of a similar nature and the species
 falls entirely within the genus. To determine if a genus claim is directed only to
 alternatives “of a similar nature,” see subsection III.B. below. Moreover, no
 problem arises in the case of a combination/subcombination situation where the
 subcombination claim avoids the prior art and the combination claim includes all the
 features of the subcombination.
 

 If, however, an independent claim does not avoid the prior art,
 then the question whether there is still an inventive link between all the claims
 dependent on that claim needs to be carefully considered. If there is no link
 remaining, an objection of lack of unity a posteriori (that is,
 arising only after assessment of the prior art) may be raised. Similar
 considerations apply in the case of a genus/species or combination/subcombination
 situation.
 

 This method for determining whether unity of invention exists is
 intended to be applied even before the commencement of the international search.
 Where a search of the prior art is made, an initial determination of unity of
 invention, based on the assumption that the claims avoid the prior art, may be
 reconsidered on the basis of the results of the search of the prior art.
 

 Alternative forms of an invention may be claimed either in a
 plurality of independent claims, or in a single claim. In the latter case, the
 presence of the independent alternatives may not be immediately apparent. In either
 case, however, the same criteria should be applied in deciding whether there is
 unity of invention. Accordingly, lack of unity of invention may exist within a
 single claim. Where the claim contains distinct embodiments that are not linked by a
 single general inventive concept, the objection as to lack of unity of invention
 should be raised. PCT Rule 13.3 does not prevent an Authority from objecting
 to alternatives being contained within a single claim on the basis of considerations
 such as clarity, the conciseness of claims or the claims fee system applicable in
 that Authority.
 

 Objection of lack of unity of invention does not normally arise if
 the combination of a number of individual elements is claimed in a single claim (as
 opposed to distinct embodiments as discussed in the paragraph immediately above),
 even if these elements seem unrelated when considered individually.
 

 III. ILLUSTRATIONS OF PARTICULAR SITUATIONS There are three particular situations for which the method for
 determining unity of invention contained in PCT Rule 13.2 is explained in
 greater detail: 
 

 
 (A) Combinations of different categories of claims;

 (B) So-called “Markush practice”; and

 (C) Intermediate and final products.

 
 Principles for the interpretation of the method contained in
 PCT Rule
 13.2 , in the context of each of those situations are set out
 below. It is understood that the principles set out below are, in all instances,
 interpretations of and not exceptions to the requirements of PCT Rule
 13.2 . 
 

 Examples to assist in understanding the interpretation on the three
 areas of special concern referred to in the preceding paragraph are set out in
 Chapter 10 of the International Search and Preliminary Examination Guidelines which
 can be obtained from the Patent Examiner’s Toolkit link or from WIPO’s website
 ( www.wipo.int/pct/en/texts/gdlines.html ).
 

 A. Combinations of Different Categories of Claims The method for determining unity of invention under
 PCT Rule
 13 shall be construed as permitting, in particular, the
 inclusion of any one of the following combinations of claims of different
 categories in the same international application: 
 

 
 (A) In addition to an independent claim for a given product,
 an independent claim for a process specially adapted for the manufacture
 of the said product, and an independent claim for a use of the said
 product; or
 

 (B) In addition to an independent claim for a given process,
 an independent claim for an apparatus or means specifically designed for
 carrying out the said process; or
 

 (C) In addition to an independent claim for a given product,
 an independent claim for a process specially adapted for the manufacture
 of the said product and an independent claim for an apparatus or means
 specifically designed for carrying out the said process.
 

 
 A process is specially adapted for the manufacture of a product
 if it inherently results in the product and an apparatus or means is
 specifically designed for carrying out a process if the contribution over the
 prior art of the apparatus or means corresponds to the contribution the process
 makes over the prior art.
 

 Thus, a process shall be considered to be specially adapted for
 the manufacture of a product if the claimed process inherently results in the
 claimed product with the technical relationship being present between the
 claimed product and claimed process. The words “specially adapted” are not
 intended to imply that the product could not also be manufactured by a different
 process.
 

 Also an apparatus or means shall be considered to be
 specifically designed for carrying out a claimed process if the contribution
 over the prior art of the apparatus or means corresponds to the contribution the
 process makes over the prior art. Consequently, it would not be sufficient that
 the apparatus or means is merely capable of being used in carrying out the
 claimed process. However, the expression “specifically designed” does not imply
 that the apparatus or means could not be used for carrying out another process,
 nor that the process could not be carried out using an alternative apparatus or
 means.
 

 More extensive combinations than those set forth above should
 be looked at carefully to ensure that the requirements of both PCT Rule
 13 (unity of invention) and PCT Article
 6 (conciseness of claims) are satisfied. In particular,
 while a single set of independent claims according to one of (A), (B), or (C)
 above is always permissible, it does not require the International Authority to
 accept a plurality of such sets which could arise by combining the provisions of
 PCT Rule
 13.3 (which provides that the determination of unity of
 invention be made without regard to whether the inventions are claimed in
 separate claims or as alternatives within a single claim), with the provisions
 set out above (thus resulting in a set based on each of a number of independent
 claims in the same category under PCT Rule 13.3 ). The
 proliferation of claims arising from a combined effect of this kind should be
 accepted only exceptionally. For example, independent claims are permissible for
 two related articles such as a transmitter and receiver; however, it does not
 follow that an applicant may include also, in the one international application,
 four additional independent claims: two for a process for the manufacture of the
 transmitter and the receiver, respectively, and two for use of the transmitter
 and receiver, respectively.
 

 A single general inventive concept must link the claims in the
 various categories and in this connection the wording above should be carefully
 noted. The link between product and process in (A) is that the process must be
 “specially adapted for the manufacture of” the product. Similarly, in (B), the
 apparatus or means claimed must be “specifically designed for” carrying out the
 process. Likewise, in (C), the process must be “specially adapted for the
 manufacture of” the product and the apparatus must be “specifically designed
 for” carrying out the process. In combinations (A) and (C), the emphasis is on,
 and the essence of the invention should primarily reside in, the product,
 whereas in combination (B) the emphasis is on, and the invention should
 primarily reside in, the process. (See Examples in Chapter 10 of the
 International Search and Preliminary Examination Guidelines which can be
 obtained from the Patent Examiner’s Toolkit link or from WIPO’s website
 ( www.wipo.int/pct/en/texts/gdlines.html .))
 

 B. “Markush Practice” The situation involving the so-called Markush practice wherein
 a single claim defines alternatives (chemical or non-chemical) is also governed
 by PCT Rule
 13.2 . In this special situation, the requirement of a
 technical interrelationship and the same or corresponding special technical
 features as defined in PCT Rule 13.2 , shall be
 considered to be met when the alternatives are of a similar nature. 
 

 When the Markush grouping is for alternatives of chemical
 compounds, they shall be regarded as being of a similar nature where the
 following criteria are fulfilled:
 

 
 (A) All alternatives have a common property or activity;
 and
 

 (B) 
 
 (1) A common structure is present, i.e., a
 significant structural element is shared by all of the
 alternatives; or
 

 
 

 (B) 
 
 (2) In cases where the common structure cannot be
 the unifying criteria, all alternatives belong to a recognized
 class of chemical compounds in the art to which the invention
 pertains.
 

 
 

 
 In paragraph (B)(1), above, the words “significant structural
 element is shared by all of the alternatives” refer to cases where the compounds
 share a common chemical structure which occupies a large portion of their
 structures, or in case the compounds have in common only a small portion of
 their structures, the commonly shared structure constitutes a structurally
 distinctive portion in view of existing prior art, and the common structure is
 essential to the common property or activity. The structural element may be a
 single component or a combination of individual components linked together.
 

 In paragraph (B)(2), above, the words “recognized class of
 chemical compounds” mean that there is an expectation from the knowledge in the
 art that members of the class will behave in the same way in the context of the
 claimed invention. In other words, each member could be substituted one for the
 other, with the expectation that the same intended result would be achieved.
 

 The fact that the alternatives of a Markush grouping can be
 differently classified should not, taken alone, be considered to be
 justification for a finding of a lack of unity of invention.
 

 When dealing with alternatives, if it can be shown that at least
 one Markush alternative is not novel over the prior art, the question of unity
 of invention should be reconsidered by the examiner. Reconsideration does not
 necessarily imply that an objection of lack of unity shall be raised. (See
 Examples in Chapter 10 of the International Search and Preliminary Examination
 Guidelines which can be obtained from the Patent Examiner’s Toolkit link or from
 WIPO’s website ( www.wipo.int/pct/
 en/texts/gdlines.html .))
 

 C. Intermediate and Final Products The situation involving intermediate and final products is also
 governed by PCT Rule 13.2 . 
 

 The term “intermediate” is intended to mean intermediate or
 starting products. Such products have the ability to be used to produce final
 products through a physical or chemical change in which the intermediate loses
 its identity.
 

 Unity of invention shall be considered to be present in the
 context of intermediate and final products where the following two conditions
 are fulfilled:
 

 
 (A) The intermediate and final products have the same
 essential structural element, in that:
 
 (1) The basic chemical structures of the
 intermediate and the final products are the same, or
 

 (2) The chemical structures of the two products are
 technically closely interrelated, the intermediate incorporating
 an essential structural element into the final product; and
 

 
 

 (B) The intermediate and final products are technically
 interrelated, this meaning that the final product is manufactured
 directly from the intermediate or is separated from it by a small number
 of intermediates all containing the same essential structural
 element.
 

 
 Unity of invention may also be considered to be present between
 intermediate and final products of which the structures are not known, for
 example, as between an intermediate having a known structure and a final product
 the structure of which is not known, or as between an intermediate of unknown
 structure and a final product of unknown structure. In order to satisfy unity in
 such cases, there must be sufficient evidence to lead one to conclude that the
 intermediate and final products are technically closely interrelated as, for
 example, when the intermediate contains the same essential element as the final
 product or incorporates an essential element into the final product.
 

 It is possible to accept in a single international application
 different intermediate products used in different processes for the preparation
 of the final product, provided that they have the same essential structural
 element.
 

 The intermediate and final products shall not be separated, in
 the process leading from one to the other, by an intermediate which is not
 new.
 

 If the same international application claims different
 intermediates for different structural parts of the final product, unity shall
 not be regarded as being present between the intermediates.
 

 If the intermediate and final products are families of
 compounds, each intermediate compound shall correspond to a compound claimed in
 the family of the final products. However, some of the final products may have
 no corresponding compound in the family of the intermediate products so that the
 two families need not be absolutely congruent.
 

 As long as unity of invention can be recognized applying the
 above interpretations, the fact that, besides the ability to be used to produce
 final products, the intermediates also exhibit other possible effects or
 activities shall not affect the decision on unity of invention. (See Examples in
 Chapter 10 of the International Search and Preliminary Examination Guidelines
 which can be obtained from the Patent Examiner’s Toolkit link or from WIPO’s
 website ( www.wipo.int/pct/en/ texts/gdlines.html .))
 

 IV. SEARCH OF ADDITIONAL INVENTIONS WITHOUT PAYMENT OF FEES If little or no additional search effort is required, reasons of
 economy may make it advisable for the examiner, while making the
 search for the main invention, to search at the same time, despite the nonpayment of
 additional fees, one or more additional inventions in the classification units
 consulted for the main invention. The international search for such additional
 inventions will then have to be completed in any further classification units which
 may be relevant, when the additional search fees have been paid. This situation may
 occur when the lack of unity of invention is found either “ a
 priori ” or “ a posteriori .” 
 

 When the examiner finds lack of unity of invention, normally, the
 applicant is invited to pay fees for the search of additional inventions. In
 exceptional circumstances, however, the examiner may be able to establish both an
 international search and a written opinion covering more than one invention with
 negligible additional work, in particular, when the inventions are conceptually very
 close. In those cases, the examiner may decide to complete the international search
 and the written opinion of the International Searching Authority for the additional
 invention(s) together with that for the invention first mentioned. In considering
 the amount of work involved, the examiner should take into account the time needed
 to create the written opinion as well as that needed to perform the search, since
 even when the additional work with regard to the search is negligible, the opposite
 may be the case for the written opinion of the International Searching Authority and
 therefore justify requesting the additional fees. If it is considered that the total
 additional work does not justify requesting additional fees, all results are
 included in the international search report (and where applicable, the written
 opinion) without inviting the applicant to pay an additional search fee in respect
 of the additional inventions searched but stating the finding of lack of unity of
 invention.
 

 V. INVITATION TO PAY ADDITIONAL FEES The search fee which the applicant is required to pay is intended
 to compensate the International Searching Authority for carrying out an
 international search and preparing a written opinion, but only where the
 international application meets the “requirement of unity of invention.” That means
 that the international application must relate to only one invention or must relate
 to a group of inventions which are so linked as to form a single general inventive
 concept ( PCT
 Articles 3(4)(iii) and 17(3)(a) ). 
 

 If the International Searching Authority finds that the
 international application does not comply with the requirement of unity of
 invention, the applicant will be informed of the lack of unity of invention by a
 communication preceding the issuance of the international search report and written
 opinion of the International Searching Authority which contains an invitation to pay
 additional search fees. (Form PCT/ISA/206 or USPTO/299 (telephone practice), see
 below). This invitation specifies the reasons the international application is not
 considered to comply with the requirement of unity of invention, identifies the
 separate inventions, and indicates the number of additional search fees and the
 amount to be paid ( PCT Rules 40.1 , 40.2(a) and (b) ). The
 International Searching Authority cannot consider the application withdrawn for lack
 of unity of invention, nor invite the applicant to amend the claims, but informs the
 applicant that, if the international search report is to be drawn up in respect of
 those inventions present other than the first mentioned, then the additional fees
 must be paid within one month from the date of the invitation to pay additional fees
 ( PCT Rule
 40.1 ). Such additional fees are payable directly to the
 International Searching Authority which is conducting the search, i.e., the USPTO,
 EPO, KIPO, IPAU, ILPO, JPO, or IPOS. The additional search fee amounts for the
 competent international searching authorities can be found in Annex D of the
 Applicant’s Guide ( www.wipo.int/pct/en/appguide ). 
 

 In the invitation to pay additional fees, the International
 Searching Authority should set out a logically presented, technical reasoning
 containing the basic considerations behind the finding of lack of unity
 ( PCT Rule
 40.1 ). 
 

 Since these payments must take place within the time limit set by
 the International Searching Authority so as to enable the observation of the time
 limit for establishing the international search report set by PCT Rule 42 ,
 the International Searching Authority should endeavor to ensure that international
 searches be made as early as possible after the receipt of the search copy. The
 International Searching Authority finally draws up the international search report
 and written opinion of the International Searching Authority on those parts of the
 international application which relate to the “main invention,” that is, the
 invention or the group of inventions so linked as to form a single general inventive
 concept first mentioned in the claims ( PCT Article 17(3)(a) ).
 Moreover, the international search report and written opinion of the International
 Searching Authority will be established also on those parts of the international
 application which relate to any invention (or any group of inventions so linked as
 to form a single general inventive concept) in respect of which the applicant has
 paid any additional fee within the prescribed time limits. 
 

 Where, within the prescribed time limit, the applicant does not pay
 any additional fees or only pays some of the additional fees indicated, certain
 parts of the international application will consequently not be searched. The lack
 of an international search report in respect of such parts of the international
 application will, in itself, have no influence on the validity of the international
 application and processing of the international application will continue, both in
 the international and in the national (regional) phases. The unsearched claims, upon
 entry into the national stage, will be considered by the examiner and may be the
 subject of a holding of lack of unity of invention.
 

 VI. PREPARATION OF THE INVITATION TO PAY ADDITIONAL FEES An Invitation to Pay Additional Fees and, Where Applicable, Protest
 Fee (Form PCT/ISA/206) is used to invite the applicant to pay additional search
 fees. In the space provided on form PCT/ISA/206, the examiner should indicate the
 number of inventions claimed in the international application covering which
 particular claims and explain why the international application is not considered to
 comply with the requirements of unity of invention. The examiner should then
 indicate the total amount of additional fees required for the search of all claimed
 inventions.
 

 Any claims found to be unsearchable under PCT Article
 17(2)(b) are not included with any invention. Unsearchable
 claims include the following: 
 

 
 (A) claims drawn to subject matter not required to be searched
 by the International Searching Authority (see MPEP §
 1843.02 ); 
 

 (B) claims in respect of which a meaningful search cannot be
 carried out (see MPEP § 1843.03 ); 
 

 (C) multiple dependent claims which do not comply with
 PCT
 Rule 6.4(a) (see MPEP §
 1843.03 ). 
 

 
 In the box provided at the top of the form, the time limit of one
 month for response is set according to PCT Rule 40.1 . Extensions of
 time are not permitted. 
 

 VII. AUTHORIZED OFFICER Form PCT/ISA/206 must be signed by an examiner with at least partial
 signatory authority.
 

 VIII. TELEPHONIC UNITY PRACTICE Telephone practice may be used to allow applicants to pay additional
 fees if
 

 
 (A) Applicant or applicant’s legal representative has a USPTO
 deposit account,
 

 (B) Applicant or the legal representative orally agrees to
 charge the additional fees to the account, and
 

 (C) A complete record of the telephone conversation is included
 with the international search report including:
 
 (1) Examiner’s name;

 (2) Authorizing attorney’s name;

 (3) Date of conversation;

 (4) Inventions for which additional fees paid; and

 (5) Deposit account number and amount to be charged.

 
 

 
 When the telephone practice is used in making lack of unity
 requirements, it is critical that the examiner orally inform applicant that there is
 no right to protest the holding of lack of unity of invention for any group of
 invention(s) for which no additional search fee has been paid.
 

 The examiner must further orally advise applicant that any protest
 to the holding of lack of unity or the amount of additional fee required must be
 filed in writing no later than one month from the mailing date of the international
 search report. The examiner should fill in the information on Form USPTO/299
 “Chapter I PCT Telephone Memorandum for Lack of Unity” as a record of the telephonic
 holding of lack of unity.
 

 If the applicant or the legal representative or agent refuses to
 either agree to a search limited to the first mentioned invention or authorize
 payment of additional fees over the telephone, or if applicant does not have a
 deposit account, the examiner should send a written invitation using Form
 PCT/ISA/206.
 

 If a written invitation is required, the examiner should, if
 possible, submit the written invitation to the Technology Center for review and
 mailing within 7 days from the date the international application is charged to the
 examiner.
 

 IX. FORM PARAGRAPHS FOR LACK OF UNITY IN INTERNATIONAL APPLICATIONS ¶ 18.05 Heading for Lack of Unity Action for PCT Applications During the International Phase (Including Species)
REQUIREMENT FOR UNITY OF INVENTION
 As provided in 
 37 CFR 1.475(a) , an international application shall relate to one invention only or to a group of inventions so linked as to form a single
 general inventive concept (“requirement of unity of invention”). Where a group of inventions is claimed in an international
 application, the requirement of unity of invention shall be fulfilled only when there is a technical relationship among those
 inventions involving one or more of the same or corresponding special technical features. The expression “special technical
 features” shall mean those technical features that define a contribution which each of the claimed inventions, considered
 as a whole, makes over the prior art.
 

 The determination whether a group of inventions is so linked as to form a single general inventive concept shall be made without
 regard to whether the inventions are claimed in separate claims or as alternatives within a single claim. See 37 CFR 1.475(e) .
 

When Claims Are Directed to Multiple Processes, Products, and/or Apparatuses:
 Products, processes of manufacture, processes of use, and apparatuses are different categories of invention. When an application
 includes claims to more than one product, process, or apparatus, the first invention of the category first mentioned in the
 claims of the application and the first recited invention of each of the other categories related thereto will be considered
 as the “main invention” in the claims. In the case of non-compliance with unity of invention and where no additional fees
 are timely paid, the international search and/or international preliminary examination, as appropriate, will be based on the
 main invention in the claims. See PCT Article 17(3)(a) , 37 CFR 1.475(d) , 37 CFR 1.476(c) 
 and 37 CFR 1.488(b)(3) .
 

 As provided in 37 CFR 1.475(b) , an international application containing claims to different categories of invention will be considered to have unity of
 invention if the claims are drawn only to one of the following combinations of categories:
 

 
 (1) A product and a process specially adapted for the manufacture of said product; or

 (2) A product and a process of use of said product; or

 (3) A product, a process specially adapted for the manufacture of the said product, and a use of the said product; or

 (4) A process and an apparatus or means specifically designed for carrying out the said process; or

 (5) A product, a process specially adapted for the manufacture of the said product, and an apparatus or means specifically designed
 for carrying out the said process.
 

 
 Otherwise, unity of invention might not be present. See 
 37 CFR 1.475(c) .
 

 This application contains the following inventions or
 groups of inventions which are not so linked as to form a single general inventive concept
 under 
 PCT Rule 13.1 .
 

 Examiner Note:
 
 1. Begin all Lack of Unity actions for PCT applications during the international phase (including species) with this heading.

 2. Follow with form paragraphs 18.06 - 18.06.02 , 18.07 - 18.07.03 , as appropriate.
 

 3. Use form paragraph 18.18 
 for lack of unity in U.S. national stage applications submitted under 35 U.S.C. 371 
 .
 
 
 

 ¶ 18.06 Lack of Unity - Three Groups of Claims

 Group [1] , claim(s) [2] , drawn to [3] .
 

 Group [4] , claim(s) [5] , drawn to [6] .
 

 Group [7] , claim(s) [8] , drawn to [9] .
 

 Examiner Note:
 
 1. In brackets 1, 4 and 7, insert Roman numerals for each Group.

 2. In brackets 2, 5 and 8, insert respective claim numbers.

 3. In brackets 3, 6 and 9, insert respective names of grouped inventions.
 
 

 ¶ 18.06.01 Lack of Unity - Two (or Additional) Groups of Claims

 Group [1] , claim(s) [2] , drawn to [3] .
 

 Group [4] , claim(s) [5] , drawn to [6] .
 

 Examiner Note:

 This form paragraph may be used alone or following form paragraph 18.06 .
 

 

 ¶ 18.06.02 Lack of Unity - One Additional Group of Claims

 Group [1] , claim(s) [2] , drawn to [3] .
 

 Examiner Note:

 This form paragraph may be used following either form paragraph 18.06 or 18.06.01 .
 

 

 ¶ 18.07 Lack of Unity - Reasons Why Inventions Lack Unity

 The groups of inventions listed above do not relate to a
 single general inventive concept under PCT Rule 13.1 because, under
 PCT Rule
 13.2 , they lack the same or corresponding special technical features for
 the following reasons: 
 

 Examiner Note:

 Follow with form paragraphs 18.07.01 through
 18.07.03 , as
 appropriate.
 

 

 ¶ 18.07.01 Same or Corresponding Technical Feature Lacking Among Groups

 [1] lack unity of invention because the groups do not share the same or corresponding technical feature.
 

 Examiner Note:
 
 1. This form paragraph may be used, for example, where the claims of Group I are directed to A + B, whereas the claims of Group
 II are directed to C + D, and thus the groups do not share a technical feature.
 

 2. In bracket 1: For international applications in the international phase , identify the groups involved by Roman numerals (e.g., “Groups I and II”) in accordance with the groups listed using form
 paragraphs 18.06 - 18.06.02 . For U.S. national stage applications under 35 U.S.C. 371 , identify the groups involved by Roman numerals (e.g., “Groups I and II”) where inventions have been grouped using form paragraphs
 18.06 - 18.06.02 , or identify the species involved where species have been listed using form paragraph 18.20 .
 
 
 

 ¶ 18.07.02 Shared Technical Feature Does Not Make a Contribution Over the Prior Art

 [1] lack unity of invention because even though the inventions of these groups require the technical feature of [2] , this technical feature is not a special technical feature as it does not make a contribution over the prior art in view
 of [3] . [4] 

 Examiner Note:
 
 1. In bracket 1: For international applications in the international phase , identify the groups involved by Roman numerals (e.g., “Groups I and II”) in accordance with the groups listed using form
 paragraphs 18.06 - 18.06.02. For U.S. national stage applications under 35 U.S.C. 371 , identify the groups involved by Roman numerals (e.g., “Groups I and II”) where inventions have been grouped using form paragraphs
 18.06 - 18.06.02 , or identify the species involved where species have been listed using form paragraph 18.20 .
 

 2. In bracket 2, identify the technical feature shared by the groups.

 3. In bracket 3, insert citation of prior art reference(s) demonstrating the shared technical feature does not make a contribution
 over the prior art. Whether a particular technical feature makes a 
 "contribution"
 
 
 over the prior art, and, therefore, constitutes a 
 "special technical feature,"
 
 
 is considered with respect to novelty and inventive step.
 

 4. In bracket 4, explain how the shared technical feature lacks novelty or inventive step in view of the reference(s).
 
 

 ¶ 18.07.03 Heading – Chemical Compound Alternatives of Markush Group Are Not of a Similar Nature

 Where a single claim defines alternatives of a Markush group, the requirement of a technical interrelationship and the same
 or corresponding special technical features as defined in Rule 13.2, is considered met when the alternatives are of a similar
 nature. When the Markush grouping is for alternatives of chemical compounds, the alternatives are regarded as being of a
 similar nature where the following criteria are fulfilled:
 

 
 (A) all alternatives have a common property or activity; AND

 (B) 
 
 (1) a common structure is present, that is, a significant
 structural element is shared by all of the alternatives; OR
 

 
 

 (B) 
 
 (2) in cases where the common structure cannot be the unifying
 criteria, all alternatives belong to a recognized class of chemical compounds in
 the art to which the invention pertains.
 

 
 

 
 The phrase “significant structural element is shared by all of the alternatives” refers to cases where the compounds share
 a common chemical structure which occupies a large portion of their structures, or in case the compounds have in common only
 a small portion of their structures, the commonly shared structure constitutes a structurally distinctive portion in view
 of existing prior art, and the common structure is essential to the common property or activity.
 

 The phrase “recognized class of chemical compounds” means that there is an expectation from the knowledge in the art that
 members of the class will behave in the same way in the context of the claimed invention, i.e. each member could be substituted
 one for the other, with the expectation that the same intended result would be achieved.
 

 Examiner Note:
 
 1. This heading should be used when the chemical alternatives of a Markush group are determined to lack unity of invention.

 2. Follow with form paragraphs listed using form paragraphs 18.07.03 a - 18.07.03 c, as appropriate. 
 
 
 

 ¶ 18.07.03a Alternatives Lack Common Property or Activity

 The chemical compounds of [1] are not regarded as being of similar nature because all of the alternatives do not share a common property or activity. [2] 

 Examiner Note:
 
 1. In bracket 1: For international applications in the
 international phase , identify the groups involved by Roman numerals (e.g.,
 “Groups I and II”) in accordance with the groups listed using form paragraphs
 18.06 -
 18.06.02 .
 For U.S. national stage applications under 35 U.S.C. 371 , identify the species involved where species have been listed using form
 paragraph 18.20 .
 

 2. In bracket 2, insert reasoning.
 
 

 ¶ 18.07.03b Alternatives Share a Common Structure - However, the Common Structure is Not a Significant Structural Element and the Alternatives
 Do Not Belong to a Recognized Class
 

 Although the chemical compounds of [1] share a common structure of [2] , the common structure is not a significant structural element because it represents only a small portion of the compound
 structures and does not constitute a structurally distinctive portion in view of [3] . Further, the compounds of these groups do not belong to a recognized class of chemical compounds. [4] 

 Examiner Note:
 
 1. In bracket 1: For international applications in the international phase , identify the groups involved by Roman numerals (e.g., “Groups I and II”) in accordance with the groups listed using form
 paragraphs 18.06 - 18.06.02 . For U.S. national stage applications under 35 U.S.C. 371 , identify the species involved where species have been listed using form paragraph 18.20 .
 

 2. In bracket 2, identify common structure.

 3. In bracket 3, insert citation of prior art reference(s) relied upon to demonstrate the commonly shared structure is not distinctive.

 4. In bracket 4, explain why the compounds do not belong to a recognized class of chemical compounds.
 
 

 ¶ 18.07.03c Alternatives Do Not Share a Common Structure or Belong to Recognized Class

 The chemical compounds of [1] are not regarded as being of similar nature because: (1) all the alternatives do not share a common structure and (2) the
 alternatives do not all belong to a recognized class of chemical compounds. [2] 

 Examiner Note:
 
 1. In bracket 1: For international applications in the international phase , identify the groups involved by Roman numerals (e.g., “Groups I and II”) in accordance with the groups listed using form
 paragraphs 18.06 - 18.06.02 . For U.S. national stage applications under 35 U.S.C. 371 , identify the species involved where species have been listed using form paragraph 18.20 .
 

 2. In bracket 2, insert reasoning.
 
 
 X. PROTEST PROCEDURE 
 PCT Administrative Instructions Section 502. 

 Transmittal of Protest Against Payment
 of Additional Fees and Decision Thereon Where International Application Is
 Considered to Lack Unity of Invention 

 The International Searching Authority shall transmit to the
 applicant, preferably at the latest together with the international search
 report, any decision which it has taken under Rule
 40.2(c) on the protest of the applicant against payment
 of additional fees where the international application is considered to lack
 unity of invention. At the same time, it shall transmit to the International
 Bureau a copy of both the protest and the decision thereon, as well as any
 request by the applicant to forward the texts of both the protest and the
 decision thereon to the designated Offices. 
 

 

 
 37 CFR 1.477 Protest to lack of unity of invention before the International Searching
 Authority. 

 
 (a) If the applicant disagrees with the holding of lack of
 unity of invention by the International Searching Authority, additional
 fees may be paid under protest, accompanied by a request for refund and
 a statement setting forth reasons for disagreement or why the required
 additional fees are considered excessive, or both ( PCT Rule
 40.2(c) ). 
 

 (b) Protest under paragraph (a) of this section will be
 examined by the Director or the Director’s designee. In the event that
 the applicant’s protest is determined to be justified, the additional
 fees or a portion thereof will be refunded.
 

 (c) An applicant who desires that a copy of the protest and
 the decision thereon accompany the international search report when
 forwarded to the Designated Offices, may notify the International
 Searching Authority to that effect any time prior to the issuance of the
 international search report. Thereafter, such notification should be
 directed to the International Bureau ( PCT Rule
 40.2(c) ). 
 

 
 

 The applicant may protest the allegation of lack of unity of
 invention or that the number of required additional fees is excessive and request a
 refund of the additional fee(s) paid. If, and to the extent that, the International
 Searching Authority finds the protest justified, the fee(s) are refunded
 ( PCT Rule
 40.2(c) ). (The additional search fees must be paid for any
 protest to be considered, but no protest fee under PCT Rule
 40.2(e) is due in the ISA/US.) 
 

 Protest of allegation of lack of unity is in the form of a reasoned
 statement accompanying payment of the additional fee, explaining why the applicant
 believes that the requirements of unity of invention are fulfilled and fully taking
 into account the reasons indicated in the invitation to pay additional fees issued
 by the International Searching Authority. Any such protest filed with the U.S.
 International Searching Authority will be decided by a Technology Center Director
 ( MPEP §
 1002.02(c) item (2)). To the extent applicant’s protest
 is found to be justified, total or partial reimbursement of the additional fee will
 be made. On the request of the applicant, the text of both the protest and the
 decision thereon is sent to the designated Offices together with the international
 search report ( 37
 CFR 1.477(c) ). 
 

 XI. NOTIFICATION OF DECISION ON PROTEST A Notification of Decision of Protest or Declaration That Protest
 Considered Not to Have Been Made (Form PCT/ISA/212) is used by the Technology Center
 (TC) to inform the applicant of the decision regarding applicant’s protest on the
 payment of additional fees concerning unity of invention. The TC checks the
 appropriate box, i.e., 1 or 2. If box 2 is checked, a clear and concise explanation
 as to why the protest concerning the unity of invention was found to be unjustified
 must be given. Since the space is limited, supplemental attachment sheet(s) should
 be incorporated whenever necessary.
 

 XII. AUTHORIZED OFFICER Form PCT/ISA/212 must be signed by a TC Director. See
 MPEP §
 1002.02(c) , item (2). 
 

 XIII. UNITY OF INVENTION - NUCLEOTIDE SEQUENCES Under 37 CFR 1.475 and
 1.499
 et seq., when claims do not comply
 with the requirement of unity of invention, i.e., when the claimed subject matter
 does not involve “one or more of the same or corresponding special technical
 features,” 37 CFR
 1.475(a) , an additional fee is required to maintain the
 claims in the same application. 37 CFR 1.476(b) . 
 

 Nucleotide sequences encoding the same protein are considered to
 satisfy the unity of invention standard and will continue to be examined
 together.
 

 Examples concerning Unity of Invention involving biotechnological
 inventions may be found in Chapter 10 of the International Search and Preliminary
 Examination Guidelines which can be obtained from the Patent Examiner’s Toolkit link
 or from the WIPO’s website ( www.wipo.int/pct/en/texts/
 gdlines.html ).
 

 [top] 

 

 

 
 

 
 

 

 

 

 
 
 
 1801-Basic Patent Cooperation Treaty (PCT) Principles 

 1802-PCT Definitions 

 1803-Reservations Under the PCT Taken by, and Notifications of Incompatibility Made by, the United States of America 

 1804-[Reserved] 

 1805-Where To File an International Application 

 1806-Applicants and Inventors 

 1807-Agent or Common Representative and General Power of Attorney 

 1808-Change in or Revocation of the Appointment of an Agent or a Common Representative 

 1809-Access to the USPTO patent electronic filing system 

 1810-Filing Date Requirements 

 1811-[Reserved] 

 1812-Elements of the International Application 

 1813 - 1816-[Reserved] 

 1817-PCT Member States 

 1818-[Reserved] 

 1819-Earlier Search 

 1820-Signature of Applicant 

 1821-The Request 

 1822-[Reserved] 

 1823-The Description 
 1823.01-Reference to Deposited Biological Material 

 1823.02-Filing Nucleotide and/or Amino Acid Sequence Listings in International Applications 

 
 

 1824-The Claims 

 1825-The Drawings 

 1826-The Abstract 

 1827-Fees 
 1827.01-Refund of International Application Fees 

 
 

 1828-Priority Claim and Document 
 1828.01-Restoration of the Right of Priority 

 1828.02-Continuation or Continuation-in-Part Indication in the Request 

 
 

 1829-[Reserved] 

 1830-International Application Transmittal Letter 

 1831-[Reserved] 

 1832-License Request for Foreign Filing Under the PCT 

 1833-[Reserved] 

 1834-Correspondence 
 1834.01-Filing of Correspondence by Facsimile 

 1834.02-Irregularities in the Mail or Electronic Communications Service 

 
 

 1835-[Reserved] 

 1836-Rectification of Obvious Mistakes 

 1837 - 1839-[Reserved] 

 1840-The International Searching Authority 
 1840.01-The European Patent Office as an International Searching Authority 

 1840.02-The Korean Intellectual Property Office as an International Searching Authority 

 1840.03-The Australian Patent Office (IP Australia) as an International Searching Authority 

 1840.04-[Reserved] 

 1840.05-The Israel Patent Office (ILPO) as an International Searching Authority 

 1840.06-The Japan Patent Office (JPO) as an International Searching Authority 

 1840.07-The Intellectual Property Office of Singapore (IPOS) as an International Searching Authority 

 
 

 1841-[Reserved] 

 1842-Basic Flow Under the PCT 

 1843-The International Search 
 1843.01-Prior Art for Chapter I Processing 

 1843.02-Certain Subject Matter Need Not Be Searched 

 1843.03-No Search Required if Claims Are Unclear 

 1843.04-Procedure for Claims Not Required To Be Searched and for Claims That Are Unclear 

 1843.05-Time Limit for Establishing the International Search Report and the Written Opinion of the International Searching Authority 

 
 

 1844-The International Search Report 
 1844.01-Preparing the International Search Report (Form PCT/ISA/210) 

 
 

 1845-Written Opinion of the International Searching Authority 
 1845.01-Preparing the Written Opinion of the International Searching Authority (Form PCT/ISA/237) 

 1845.02-Notification of Transmittal of the International Search Report and the Written Opinion of the International Searching Authority,
 or the Declaration (Form PCT/ISA/220) 

 
 

 1846 - 1847-[Reserved] 

 1848-Sequence Listings 

 1849-[Reserved] 

 1850-Unity of Invention Before the International Searching Authority 

 1851-Identification of Patent Documents 

 1852-Taking Into Account Results of Earlier Search(es) 

 1853-Amendment Under PCT Article 19 

 1854 - 1855-[Reserved] 

 1856-Supplementary International Searches 

 1857-International Publication 

 1858-[Reserved] 

 1859-Withdrawal of International Application, Designations, or Priority Claims 

 1860-International Preliminary Examination Procedure 

 1861-[Reserved] 

 1862-Agreement With the International Bureau To Serve as an International Preliminary Examining Authority 

 1863-[Reserved] 

 1864-The Demand and Preparation for Filing of Demand 
 1864.01-Amendments Filed Under PCT Article 34 

 1864.02-Applicant’s Right To File a Demand 

 1864.03-States Which May Be Elected 

 1864.04-Agent’s Right To Act 

 
 

 1865-Filing of Demand 

 1866-[Reserved] 

 1867-Preliminary Examination Fees 

 1868-Correction of Defects in the Demand 

 1869-Notification to International Bureau of Demand 

 1870-Priority Document and Translation Thereof 

 1871-Processing Amendments Filed Under Article 19 and Article 34 Prior to or at the Start of International Preliminary Examination 

 1872-Availability of the International Application File for International Preliminary Examination by the Examining Corps 

 1873-[Reserved] 

 1874-Determination if International Preliminary Examination Is Required and Possible 

 1875-Unity of Invention Before the International Preliminary Examining Authority 
 1875.01-Preparation of Invitation Concerning Unity 

 1875.02-Reply to Invitation Concerning Lack of Unity of Invention 

 
 

 1876-Notation of Errors and Informalities by the Examiner 
 1876.01-Request for Rectification and Notification of Action Thereon 

 
 

 1877-Nucleotide and/or Amino Acid Sequence Listings During the International Preliminary Examination 

 1878-Preparation of the Written Opinion of the International Preliminary Examining Authority 
 1878.01-Includes Subsections Regarding Prior Art, Novelty, Inventive Step, and Industrial Applicability for Purposes of the Written
 Opinion and the International Preliminary Examination Report 
 1878.01(a)-Prior Art for Purposes of the Written Opinion and the International Preliminary Examination Report 
 1878.01(a)(1)-Novelty for Purposes of the Written Opinion and the International Preliminary Examination Report 

 1878.01(a)(2)-Inventive Step for Purposes of the Written Opinion and the International Preliminary Examination Report 

 1878.01(a)(3)-Industrial Applicability for Purposes of the Written Opinion and the International Preliminary Examination Report 

 
 

 
 

 1878.02-Reply to the Written Opinion of the ISA or IPEA 

 
 

 1879-Preparation of the International Preliminary Examination Report 
 1879.01-Time Limit for Preparing Report 

 1879.02-Transmittal of the International Preliminary Examination Report and Related Documents 

 1879.03-Translations 

 1879.04-Confidential Nature of the Report 

 
 

 1880-Withdrawal of Demand or Election 

 1881-Receipt of Notice of Election and Preliminary Examination Report by the United States Patent and Trademark Office 

 1882 - 1892-[Reserved] 

 1893-National Stage (U.S. National Application Filed Under 35 U.S.C. 371) 
 1893.01-Commencement and Entry 
 1893.01(a)-Entry via the U.S. Designated or Elected Office 
 1893.01(a)(1)-Submissions Required by 30 Months from the Priority Date 

 1893.01(a)(2)-Article 19 Amendment (Filed With the International Bureau) 

 1893.01(a)(3)-Article 34 Amendments (Filed with the International Preliminary Examining Authority) 

 1893.01(a)(4)-Claim Amendment (Filed With the U.S. Designated or Elected Office) 

 
 

 1893.01(b)-Applicant for a U.S. National Stage Application 

 1893.01(c)-Fees 

 1893.01(d)-Translation 

 1893.01(e)-Inventor’s Oath or Declaration 

 
 

 1893.02-Abandonment 

 1893.03-Prosecution of U.S. National Stage Applications Before the Examiner 
 1893.03(a)-How To Identify That an Application Is a U.S. National Stage Application 

 1893.03(b)-The Filing Date of a U.S. National Stage Application 

 1893.03(c)-The Priority Date, Priority Claim, and Priority Papers for a U.S. National Stage Application 

 1893.03(d)-Unity of Invention 

 1893.03(e)-Documents Received from the International Bureau and Placed in a U.S. National Stage Application File 
 1893.03(e)(1)-Title of the Invention 

 
 

 1893.03(f)-Drawings and PCT Rule 11 

 1893.03(g)-Information Disclosure Statement in a National Stage Application 

 
 

 
 

 1894-[Reserved] 

 1895-A Continuation, Divisional, or Continuation- in- Part Application of a PCT Application Designating the United States 
 1895.01-Handling of and Considerations in the Handling of Continuations, Divisions, and Continuations-In-Part of PCT Applications 

 
 

 1896-The Differences Between a National Application Filed Under 35 U.S.C. 111(a) and a National Stage Application Submitted Under
 35 U.S.C. 371 

 

 

 
 

 
 
 

 
 

 

 
 
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