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March 29, 2008

Mixed Claim Types

Both the USPTO and the courts proscribe claims mixing statutory claim classes as both unpatentable subject matter under §101 and indefinite under §112 ¶2. But, as is often the case with claim construction, the line may seem fuzzy. Herein a guide.

The November 2005 IPXL Holdings v. Amazon CAFC ruling found claim 25 in the notorious Amazon 1-click patent (6,149,055) indefinite.

25. The system of claim 2 [including an input means] wherein the predicted transaction information comprises both a transaction type and transaction parameters associated with that transaction type, and the user uses the input means to either change the predicted transaction information or accept the displayed transaction type and transaction parameters.

The district court found that claim 25 is indefinite under 35 U.S.C. § 112, as it attempts to claim both a system and a method for using that system. Section 112, paragraph 2, requires that the claims of a patent "particularly point[] out and distinctly claim[] the subject matter which the applicant regards as his invention." 35 U.S.C. § 112 (2000). A claim is considered indefinite if it does not reasonably apprise those skilled in the art of its scope. Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1217 (Fed. Cir. 1991).

The problem was that the claim could have been read either as a system claim or method claim.

Thus, it is unclear whether infringement of claim 25 occurs when one creates a system that allows the user to change the predicted transaction information or accept the displayed transaction, or whether infringement occurs when the user actually uses the input means to change transaction information or uses the input means to accept a displayed transaction.

Xerox got both barrels in a non-precedential BPAI toss in 2005, just after the IPXL Holdings v. Amazon.com dustup.

MPEP 2173.05(p) appears at first glance Janus-like on the topic, but does split the hairs properly. While a product-by-process claim is copasetic, an apparatus claim including method steps is non-statutory.

2173.05(p) Claim Directed to Product-By- Process or Product and Process [R-5]

There are many situations where claims are permissively drafted to include a reference to more than one statutory class of invention.


A product-by-process claim, which is a product claim that defines the claimed product in terms of the process by which it is made, is proper. In re Luck, 476 F.2d 650, 177 USPQ 523 (CCPA 1973); In re Pilkington, 411 F.2d 1345, 162 USPQ 145 (CCPA 1969); In re Steppan, 394 F.2d 1013, 156 USPQ 143 (CCPA 1967). A claim to a device, apparatus, manufacture, or composition of matter may contain a reference to the process in which it is intended to be used without being objectionable under 35 U.S.C. 112, second paragraph, so long as it is clear that the claim is directed to the product and not the process.

An applicant may present claims of varying scope even if it is necessary to describe the claimed product in product-by-process terms. Ex parte Pantzer, 176 USPQ 141 (Bd. App. 1972).


A single claim which claims both an apparatus and the method steps of using the apparatus is indefinite under 35 U.S.C. 112, second paragraph. IPXL Holdings v. Amazon.com, Inc., 430 F.2d 1377, 1384, 77 USPQ2d 1140, 1145 (Fed. Cir. 2005); Ex parte Lyell, 17 USPQ2d 1548 (Bd. Pat. App. & Inter. 1990) (claim directed to an automatic transmission workstand and the method of using it held ambiguous and properly rejected under 35 U.S.C. 112, second paragraph).

Such claims may also be rejected under 35 U.S.C. 101 based on the theory that the claim is directed to neither a "process" nor a "machine," but rather embraces or overlaps two different statutory classes of invention set forth in 35 U.S.C. 101 which is drafted so as to set forth the statutory classes of invention in the alternative only. Id. at 1551.

MPEP 2114 elucidates that apparatus claim validity relies solely upon the structure of the device itself, irrespective of function. If apparatus claim novelty relies upon functional language, the claim is invalid.

2114 Apparatus and Article Claims - Functional Language [R-1]

For a discussion of case law which provides guidance in interpreting the functional portion of means-plus-function limitations see MPEP § 2181 - § 2186.

While features of an apparatus may be recited either structurally or functionally, claims directed to an apparatus must be distinguished from the prior art in terms of structure rather than function. In re Schreiber, 128 F.3d 1473, 1477-78, 44 USPQ2d 1429, 1431-32 (Fed. Cir. 1997) (The absence of a disclosure in a prior art reference relating to function did not defeat the Board's finding of anticipation of claimed apparatus because the limitations at issue were found to be inherent in the prior art reference); see also In re Swinehart, 439 F.2d 210, 212-13, 169 USPQ 226, 228-29 (CCPA 1971);< In re Danly, 263 F.2d 844, 847, 120 USPQ 528, 531 (CCPA 1959). "[A]pparatus claims cover what a device is, not what a device does." Hewlett-Packard Co. v. Bausch & Lomb Inc., 909 F.2d 1464, 1469, 15 USPQ2d 1525, 1528 (Fed. Cir. 1990) (emphasis in original).

A claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus" if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987) (The preamble of claim 1 recited that the apparatus was "for mixing flowing developer material" and the body of the claim recited "means for mixing ..., said mixing means being stationary and completely submerged in the developer material". The claim was rejected over a reference which taught all the structural limitations of the claim for the intended use of mixing flowing developer. However, the mixer was only partially submerged in the developer material. The Board held that the amount of submersion is immaterial to the structure of the mixer and thus the claim was properly rejected.).

Even if the prior art device performs all the functions recited in the claim, the prior art cannot anticipate the claim if there is any structural difference. It should be noted, however, that means plus function limitations are met by structures which are equivalent to the corresponding structures recited in the specification. In re Ruskin, 347 F.2d 843, 146 USPQ 211 (CCPA 1965) as implicitly modified by In re Donaldson, 16 F.3d 1189, 29 USPQ2d 1845 (Fed. Cir. 1994). See also In re Robertson, 169 F.3d 743, 745, 49 USPQ2d 1949, 1951 (Fed. Cir. 1999) (The claims were drawn to a disposable diaper having three fastening elements. The reference disclosed two fastening elements that could perform the same function as the three fastening elements in the claims. The court construed the claims to require three separate elements and held that the reference did not disclose a separate third fastening element, either expressly or inherently.).

MPEP 2106 IV. B. "Determine Whether the Claimed Invention Falls Within An Enumerated Statutory Category," in disclosing examination guidelines, skirts the issue, failing to give guidance as to how to determine a mixed-type claim. 2106 is best considered an aside to the subject.

For example, a claimed invention may be a combination of devices that appear to be directed to a machine and one or more steps of the functions performed by the machine. Such instances of mixed attributes, although potentially confusing as to which category of patentable subject matter the claim belongs, does not affect the analysis to be performed by USPTO personnel. Note that an apparatus claim with process steps is not classified as a "hybrid" claim; instead, it is simply an apparatus claim including functional limitations. See, e.g., R.A.C.C. Indus. v. Stun-Tech, Inc., 178 F.3d 1309 (Fed. Cir. 1998) (unpublished).

While nominally a claim preamble states the statutory class, preambles are only considered a limitation if substantial; most are not. Hence, a typical preamble carries little or no weight in claim construction. Analogously, this would be the same in determining whether a claim is an unstatutory mixed type.

The cutting edge for an non-statutory dual-matter claim is whether the claim could be reasonably read "either-or" - interpretable within two of the four categories of patentable subject matter: "process, machine, manufacture, or composition of matter" (35 U.S.C. §101). Another viewpoint would be to answer the question: what is crucial, specifically novel, about the claim that merits its patentability? If the answer lies in a different claim type than the claim nominally is, the claim is invalid.

Posted by Patent Hawk at March 29, 2008 12:11 AM | Claim Construction


How about posting the claims at issue?

Posted by: Steve Sereboff at March 29, 2008 5:46 AM

Is there any way of dealing with claims of this type that somehow slipped their way past an Examiner into an issued patent, besides waiting to get sued and then putting forth an affirmative defense of claim invalidity?

Posted by: James at November 11, 2009 5:20 PM


Posted by: 6000 at November 12, 2009 2:01 PM