A Technique to Assert the Patentable Weight of a Claim Preamble

PATENTABLY DEFINED
THE PATENT PROSECUTION BLOG OF MICHAEL E. KONDOUDIS
A Technique to Assert the
Patentable Weight of a Claim Preamble
By MICHAEL E. KONDOUDIS
The Patentable Weight of a Claim Preamble
Generally, during the examination of an application, an Examiner
attempts to rebut the novelty and non-obviousness of a claim by
identifying, in the prior art, teachings or suggestions of each
feature of that claim. Some claim features, however, may be ignored
in this analysis. These features are said not to be entitled to any
“patentable weight.”
One of the claim components that frequently gives rise to disputes
about patentable weight is a claim’s preamble (e.g., a device for)
which, along with a transitional phrase (e.g., comprising) and a body
(e.g., a wheel), constitutes a claim.
Examiners generally decline to consider the novelty and non-
obviousness of a claim’s preamble because preambles tend to only
provide a context or a purpose for a claimed invention. Similarly,
Examiners often dismiss as unpersuasive patentability arguments
based on features recited in a preamble. This is, however, by no
means a per se rule. Indeed, there are circumstances when features
in a claim’s preamble must be given patentable weight.
Consequently, when an Applicant relies on features in a preamble
to traverse a claim rejection, it often becomes necessary to explain
to the Examiner why those features are entitled to patentable
weight.
The Test and the Law
There is no litmus test for determining whether a preamble should
be given patentable weight. Basically, a claim preamble is said to be
as important as the claim as a whole suggests.
A preamble is entitled to patentable weight when it is “necessary to
give life, meaning, and vitality” to the claim. Pitney Bowes, Inc. v.
Hewlett-Packard Co., 182 F.3d 1298, 1305 (Fed. Cir. 1999). The
Federal Circuit has held that a preamble may give “life, meaning and
vitality” to a claim either: (1) explicitly (the claim expressly uses
the preamble and the body of the claim to define the claimed
invention); or (2) implicitly (proper construction of the claim
requires reference to the preamble). So, when an Applicant uses
the body of a claim and the preamble to define the claimed subject
matter, the preamble should be accorded patentable weight.
The Law Office of Michael E. Kondoudis, PC
A Professional Corporation Focused Exclusively on Intellectual Property Law
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PATENTABLY DEFINED
THE PATENT PROSECUTION BLOG OF MICHAEL E. KONDOUDIS
Conversely, when the body of the claim “fully and intrinsically”
sets forth the claimed invention, the preamble may not be entitled
to patentable weight. As the Pitney Bowes court instructed, when a
preamble “offers no distinct definition of any of the claimed
invention’s limitations, but rather merely states . . . the purpose or
intended use of the invention,” then the preamble cannot be read as
a limitation on a claim.
The MPEP addresses the patentable weight of preambles in section
2111.02, which provides the following limited, specific guidance:
1. Preambles that limit structure must be given patentable weight
(MPEP 2111.02(I)); and
2. Preambles reciting a purpose or an intended use may be given
patentable weight (MPEP 2111.02(II). Specifically, features in the
preamble reciting the purpose or intended use of the claimed
invention must be evaluated to determine whether the recited
purpose or intended use results in a structural difference (or, in
the case of process claims, manipulative difference) between the
claimed invention and the cited art. If so, the recitation serves to
limit the claim.
An Example of an Argument that a Claim Preamble Should Be Given
Patentable Weight
Presume that claim 1 recites the following:
A method of transmitting a packet over a system including a client
and a source device, the packet including a source address and a
destination address, the method comprising:
assigning, by the source device, one of plural trees to broadcast
the packet to the destination address; …
associating with the packet an identifier indicative of one of the
trees.
An appropriate response to an Office Action that dismisses a
patentability argument based on features recited in the preamble
(that the cited art does not teach or suggest a packet that includes
a destination address), may be the following:
Applicant notes, at page 4 of the Office Action, the Office’s
contention that features recited in the preamble of claim 1,
and in particular a packet “including … a destination address”
need not be accorded any patentable weight. This contention
The Law Office of Michael E. Kondoudis, PC
A Professional Corporation Focused Exclusively on Intellectual Property Law
www.mekiplaw.com
mkondoudis@mekiplaw.com
+1-202-349-9850
© 2007-2008, Michael E. Kondoudis, All Rights Reserved

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PATENTABLY DEFINED
THE PATENT PROSECUTION BLOG OF MICHAEL E. KONDOUDIS
is respectfully traversed as being incorrect as a matter of
law.
It is established law that when a preamble of a claim
provides more than just context for the claimed invention,
that preamble should be given patentable weight. Indeed,
when, as is the case here, the body of the claim expressly
refers to features in a preamble and uses those referenced
features to define the claimed invention, it is legal error not
to give that preamble patentable weight.
Claim 1 recites “assigning … [one tree] to broadcast a
packet to a destination address.” And, this packet is expressly
defined by the claim preamble to include that destination
address. Thus, the body of claim 1 expressly incorporates by
reference the preamble feature of a packet that includes a
destination address. In this way, the body of the claim depends
on the preamble for completeness and gives life, meaning, and
vitality to this claim. For this reason alone, the preamble of
claim 1 should be afforded patentable weight. See MPEP
2112.02(II).
The preamble of claim 1, however, should be afforded
patentable weight for another reason. The MPEP instructs
that preambles that limit structure must be given patentable
weight. (See MPEP 2112.02(I)). The incorporation by reference
of the preamble feature of a packet “including … a
destination address” defines a packet that has a data
structure not found in the applied art. Thus, the preamble of
claim 1 must be given patentable weight.
The Law Office of Michael E. Kondoudis, PC
A Professional Corporation Focused Exclusively on Intellectual Property Law
www.mekiplaw.com
mkondoudis@mekiplaw.com
+1-202-349-9850
© 2007-2008, Michael E. Kondoudis, All Rights Reserved

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