by: Joseph Page
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Reference Numerals in Claims

What do these mean and what implications do they have on patent scope?

Reference Numerals in Claims
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US vs. EU - claims references

Use of reference numerals in claims can limit scope in U.S.

National patent systems have evolved under various influences and philosophy. We can see this clearly today with particular regard to software patents where Europe has taken a strikingly different and perhaps more pessimistic course than the United States. Although some 'harmonization' has occurred lately, the United States remains far more bullish with regard to patents for subject matter such as software and Internet technologies. Other far more subtle differences between national patent systems can nevertheless have important effect on the overall strength of your patent portfolio. Among these subtle differences includes use of reference numerals in claims. While quite common in European patent practice, it is far less so in US patent practice.
Reference numerals in claims is readily found in patents being issued today in Europe . US rules do not strictly preclude such use, but due to potential limitations to patent claims scope, most US practitioners will not use these in normal practice.
A serious defect occurs when an European style patent application is converted to and prosecuted in the United States as a US patent application where the reference numerals are maintained. In many cases, the reference numerals which are a normal part of the European application are left in the US application to great disadvantage. In Europe, reference numerals can actually increase claim scope or they have little or no effect on claim scope. Conversely in the US, reference numerals in claims can profoundly limit claim scope.
While it is very simple to remove reference numerals from European patent claims to form a US style patent application, surprisingly many patent firms do not bother to do this important conversion. Which begs the question: "which other modifications are being ignored when your European applications are converted to and prosecuted in the United States"?
Due to particulars of each national patent system, it is necessary to take great care and apply modifications to an original patent application prior to prosecuting it under another national patent system. Although PCT and other harmonization provisions permit a single application form to be prosecuted under multiple patent systems, these are mostly directed to matters of form regarding supporting documentation and process. However, with regard to substance of the disclosure and claims portions of the document, very serious detrimental results can occur when even simple precautions are not respected.
If your European applications are being prosecuted in the US with the claims reference numerals included, you might instruct your representative to adjust this for future applications. Alternatively, you might contact Integrity IP to learn more of this and other important differences between patent practice in the US and Europe.
Why are reference numerals in patent claims a 'defect' under the US patent system?
In the United States when patent claims are analyzed for infringement, they are parsed quite strictly and literally word-by-word. Any meaning or sense appearing in the claim which tends to narrow the scope of any claim term is applied strongly against the interest of the inventor/applicant - and in favor of the public. Under European systems, this rule is not as strictly applied. Thus in the US, one small error in any claim term can be greatly prejudicial against the patentee. A US patentee carries a very high burden of precisely choosing the words to define his invention in patent claims. This is not so much the case in Europe where patent claim terms may be more liberally interpreted in a broader scope and in view of the entire disclosure. The European patentee has less of a burden towards precision and the general meaning of the invention as it intended by the inventor may be gleaned from claims and the specification. The court looks more at the 'four corners' of the patent claims and specification to gain the 'overall' picture of the essence of the invention. Slight modifying or limiting terms are less prejudicial against claim scope. This is where infringement is determined under European systems.
Accordingly, when reference numerals are used in European claims, any analysis for infringement is enlarged because the claim can be understood in view of the appended drawings and description as well as the claims term. Conversely under a US infringement analysis, use of reference numerals tends to import further limitations into claim terms but does not enlarge them. Thus, use of reference numerals in US claims can operate to further limit claim scope but rarely can it enlarge claim scope. For this reason among others, in nearly all cases it is preferable to omit reference numerals in the claims of US patent applications.
It isn't usually a difficult task to remove reference numerals from the European application to convert it to a US style patent application. In a great percentage of cases – simply deleting the reference numerals without other modification is a perfect solution. Removal of the reference numerals does not usually impart any new meaning to claim terms. However, in some other cases slight additional modifications to the specification and/or claims must be made to support such changes.
A special note for those experts in patent prosecution: While the U.S. MPEP at 608.01(m) suggests that reference numerals will have 'no effect one claims scope' – you should remain mindful that the MPEP is written as a guide for a patent examiner whose task is to determine patentability. In view of the patentability question, and the tests to be performed in coming to a patentability determination, this may be true. However, the MPEP does not give guidance regarding matters of patent infringement – an entirely different question with different tests and different standards. Those standards are not set and used by the MPEP but rather the Federal District and Circuit courts. Accordingly, claims with reference numerals will be examined as if those numbers were not present – however, once those claims are subject to any infringement determination, those reference numerals will operate to drag further limitations, sometimes severe, into the claims.
A compound but related problem still further operates to render US patent claims defective where the identical claim is perfectly sound in a European system. Consider the claim term "Balken (21I; 21II; 21III; 21VI)" from the German patent the claim in its entirety is:
"2. Entwerteaufdruck nach Anspruch 1, dadurch gekennzeichnet, dass das erste Druckbild (21) wenigstens drei parallele Balken (21I; 21II; 21III; 21VI) aufweist, und der Abstand zwischen jeweils zwei benachbarten Balken (21I; 21II; 21III; 21VI) gleich ist."
This claim would be considered totally unpatentable in US patent practice as it violates the principle of 'alternative claiming' – unless 21I, 21II, 21III, and 21VI are identical – and if they are identical, then what is the distinction the superscript designates? If there is any variance whatever in the claim element, then these claims would necessarily be excluded in under US rules as ambiguous. Yet this claim form is now common in Europe.
Here is yet another version of a European patent of this type of alternative claiming in Europe where several alternative versions are seemingly incorporated in a single claim. This claim structure would not be allowed in the U.S.
" Einrichtung zur Reifendruck-•Uberwachung mit einem ein reifendruckabh•angiges Signal abgebenden Druckmessglied (4; 11; 21, 34) und einer bei Unterschreiten eines Reifendruck-Grenzwertes von dem Signal des Druckmessgliedes (4; 11; 21, 34) bet•atigten Auswerteeinrichtung (2; 32, 24, 29, 26, 27) sowie mit einem das Signal des Druckmessgliedes (4; 11; 21, 34) temperaturabh•angig korrigierenden Korrekturglied (2, 3; 21, 34), dadurch gekennzeichnet, dass das Korrekturglied (2, 3; 21, 34) der ausserhalb des Reifens (1) herrschenden Temperatur ausgesetzt ist".
Even if you speak perfect German, this claim makes little or no sense under the US system which only permits alternative claim elements in a special form (Markush Group). If "(2; 32, 24, 29, 26, 27)" all refer to the identical element, but not various versions thereof, then the claim might survive in a US examination. However, the ambiguity introduced in this construction might render the claim weak under US rules. Removing all reference numerals may be a perfect solution.
Curiously, these reference numerals have an even greater complex nature to them. Look carefully to find use of ';' and ',' between the various numerals. This syntax imparts additional meaning useful in the European system but having no meaning at all in the US system.
It is most certainly normal practice to prosecute an invention under two distinct patent systems such as United States system and the European system. However, special care should be taken to produce two versions of the application in view of particular rules in each patent system. Even something so simple as reference numerals in claims can have a profound ultimate effect on patent coverage. If your patent representative is prosecuting your European applications in the US without taking even this minor precaution (i.e. deleting the numerals from claims) you might want to consider what the ultimate result will be. When these patents are subject to litigation, you'll be greatly disappointed to find your protection reduced for such a minor deviation.
While this working note is meant to illustrate the importance of variance between rules of national patent systems, it should be understood that reference numerals are merely the beginning. Many other significant differences in rules can have great effect on the protection afforded under different national patent systems even where the application is otherwise identical.

See for examples: EP1570986B1; EP0860545A; and EP1595565.

EP2283936A1 - Voiding stamp, postage item with same and method for applying and inspecting voiding stamps

EP0418495A1 – Tyre pressure control apparatus

Printer version of this IIP Patent TopicCopyright IIP 2011
Comments on the patent topic: Reference Numerals in Claims
In Hochstein v. Microsoft Corp., 2009 WL 1838975, No. 04-73071 (E.D. Mich. June 22, 2009), the court held that attaching the reference numerals 108, 124 to the term “player port logic circuits” did not limit the logic circuits to shift registers where the spec recited “shift registers 108, 124.” The inclusion of the reference numerals helped persuade the court that the meaning of the modifier “player port” was clear, as shift registers 108, 124 were connected to a player port. Thus, “player port logic circuits (108, 124)” meant logic circuits “operatively associated with the player ports.” So the patentee incidentally benefited from the inclusion of the reference numerals as a basis for 112 support. However, the reference numerals did not limit the type of logic circuits to “shift registers.” To the contrary, the court even went so far as to explicitly include the expansive language “without limitation as to what type of logic they perform” in its construction of the disputed term. Granted, this is an unpublished district court case, but I have been unable to find a more definitive judicial precedent on point. Are you aware of any?
5/20/2013 5:46:39 PM
I've noticed these reference numerals and thought them awdward.  Do they ever help the claim?  If not, then why does Europe use them?
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