Ex Parte Wang

Patent Trial and Appeal Board

Apr 15, 2014

12014718 (P.T.A.B. Apr. 15, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE PATENT TRIAL AND APPEAL BOARD
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Ex parte CHEUKSAN EDWARD WANG
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Appeal 2011-010670
Application 12/014,718
Technology Center 2100
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Before MAHSHID D. SAADAT, BRUCE R. WINSOR, and J. JOHN LEE,
Administrative Patent Judges.

LEE, Administrative Patent Judge.

DECISION ON APPEAL

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STATEMENT OF THE CASE
Appellant1 appeals under 35 U.S.C. § 134 from the final rejection of
claims 1-9 and 11-28. Claim 10 is cancelled. We have jurisdiction over the
appeal under 35 U.S.C. § 6(b).
We affirm-in-part.

CLAIMED SUBJECT MATTER
Independent claims 1 and 12 are exemplary of the claims on appeal.
Claim 1 recites:
1. A method performed on a server system having one or
more processors and memory storing one or more programs for
execution by the one or more processors to perform the method,
comprising:
retrieving a list of results responsive to a search request
from a user at a first client;
applying a multi-user Bloom filter to results in the list of
results to identify one or more first results, if any, in the list of
results that the user has previously accessed;
generating a result list comprising at least a portion of the
list of results, based at least in part on the identified one or
more first results; and
sending the result list to the first client.
Claim 12 recites:
12. A method performed on a server system having one or
more processors and memory storing one or more programs for
execution by the one or more processors to perform the method,
comprising:
in response to search requests from each of a plurality of
users at respective clients, retrieving a list of results responsive
to each of the search request, including a first list of results

1 Appellant identifies Google Inc. as the real party in interest. (App. Br. 4.)
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responsive to a first search request from a first user at a first
client and a second list of results responsive to a second search
request from a second user at a second client;
filtering results in the first list of results and results in the
second list of results with a shared Bloom filter to produce a
first filtered result list, comprising at least a portion of the first
list of results, and a second filtered result list, comprising at
least a portion of the second list of results;
sending the first filtered result list to the first client; and
sending the second filtered result list to the second client.

REJECTION
Claims 1-9 and 11-28 stand rejected under 35 U.S.C. § 102(e) as
being anticipated by Van Vleet (US 7,565,425 B2, filed July 2, 2003).

ANALYSIS
Claims 1, 2, 4-8, 11, 24, and 25
Appellant argues the patentability of independent claims 1, 24, and 25
together. (App. Br. 17-24.) Further, Appellant does not separately argue the
patentability of dependent claims 2, 4-8, and 11. As such, we consider the
issues presented regarding these claims with reference to claim 1.
The key claim term at issue with respect to claim 1 is “multi-user
Bloom filter.” Appellant does not contest the Examiner’s finding that Van
Vleet discloses Bloom filters applied to search results. Rather, Appellant
asserts that Van Vleet only discloses “user-specific” Bloom filters, which are
allegedly distinct from the claimed “multi-user” Bloom filter.2 (App. Br. 17-

2 The Specification describes the typical workings of a generic Bloom filter,
a “well known computer science mechanism.” (Spec. ¶¶ 19-21.)
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23.) The Examiner found that Van Vleet discloses a system where Bloom
filters are stored and applied to a plurality of users, i.e., “multi-user” Bloom
filters. (Ans. 3, 7.) In particular, the Examiner relied on Van Vleet’s
disclosure that “[a] given user need not be an individual, but may, for
example, be a group of individuals that share a user computer 36 or a user
account.” (Van Vleet, col. 4 ll. 7-9.)
We are not persuaded the Examiner erred. Both Appellant and the
Examiner agree that Van Vleet discloses applying a Bloom filter to a single
user account where multiple individuals use the same account. The only
dispute is whether the term “multi-user Bloom filter” should be construed to
encompass such a Bloom filter. In construing “multi-user Bloom filter,” we
give the term its broadest reasonable interpretation in light of the
Specification. In re Am. Acad. of Sci. Tech Ctr., 367 F.3d 1359, 1364 (Fed.
Cir. 2004). The term “multi-user Bloom filter” does not appear in the
Specification. Thus, we construe “multi-user Bloom filter” according to its
ordinary meaning, a Bloom filter applied to multiple users. As the Examiner
found, Van Vleet discloses applying a Bloom filter to the search results of a
user account that may be used by multiple individuals, thereby applying the
Bloom filter to multiple users. (Ans. 7.)
Appellant argues the claim itself compels a narrower construction
requiring that a “multi-user” Bloom filter be able to distinguish between
specific individuals in a group of individuals using a single user account.
(App. Br. 23; Reply Br. 7-8.) However, claim 1 only recites that the “multi-
user” Bloom filter is applied to “identify one or more first results, if any, in
the list of results that the user has previously accessed”—the claim does not
require that only the results the individual user has previously accessed be
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identified. As Appellant admits (id.), the Bloom filter of Van Vleet will
identify results previously accessed by all of the individual users using the
same user account, which necessarily includes the results accessed by any
particular one of those users as recited in claim 1. Appellant further points
to portions of the Specification describing an embodiment of the claimed
invention (App. Br. 14 (citing Spec. ¶ 36)), but limitations from an
embodiment should not be imported into the claims absent clear disclaimer
in the Specification. Am. Acad. of Sci., 367 F.3d at 1369.
For the above reasons, the Examiner’s rejection of claims 1, 2, 4-8,
11, 24, and 25 as being anticipated by Van Vleet is sustained.

Claim 9
Appellant separately argues the patentability of dependent claim 9,
asserting that Van Vleet fails to disclose “a plurality of Bloom filters . . .
wherein each Bloom filter in the plurality of Bloom filters corresponds to a
respective plurality of users.” (App. Br. 31-32.) The Examiner found that
Van Vleet discloses a plurality of Bloom filters (Ans. 5 (citing Van Vleet,
col. 13 ll. 5-17)) and, as already discussed, that the Bloom filters of Van
Vleet are “multi-user” Bloom filters because they are applied to multiple
users on the same user account (Ans. 7).
We are not persuaded the Examiner erred. Appellant admits Van
Vleet discloses a plurality of Bloom filters. (App. Br. 22.) Claim 9 merely
recites that each Bloom filter “corresponds to a respective plurality of
users.” For similar reasons as discussed for claim 1, we agree with the
Examiner’s finding that Van Vleet discloses Bloom filters where each
corresponds to a plurality of users when multiple individuals use a single
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user account. Appellant does not identify any evidence or disclosure in the
Specification compelling a narrower interpretation of the claim.
Thus, the Examiner’s rejection of claim 9 as being anticipated by Van
Vleet is sustained.

Claims 16, 17, and 19-23
Appellant argues the patentability of claims 16-23 together (App. Br.
26-27), but provides further arguments for patentability for claim 18 (id. 29).
Thus, we analyze the issues presented regarding claims 16, 17, and 19-23
with reference to claim 16, and we analyze claim 18 separately.
Similar to claim 1, Appellant argues the Examiner erred in finding
claims 16, 17, and 19-23 anticipated because Van Vleet only discloses “user-
specific” Bloom filters. (Id. 26-27.) Independent claim 16 recites “updating
a Bloom filter associated with the plurality of clients to indicate each
respective item sent to a respective client . . .” (emphases added). The
Examiner found that Van Vleet discloses this feature in its discussion of a
process of updating an event history where all the events (e.g., accessing a
website) for a particular user ID is recorded in one or more Bloom filters for
that user account. (Ans. 6, 8 (citing Van Vleet, fig. 2, col. 6 ll. 31-45).)
Further, as discussed supra and as found by the Examiner, Van Vleet
discloses that a user account may be used by multiple individuals.
We are not persuaded the Examiner’s findings or conclusion were
erroneous. Similar to claim 9 where the Bloom filter “corresponds” to a
plurality of users, claim 16 only requires that the Bloom filter be “associated
with” a plurality of clients. While claim 16 also requires that the Bloom
filter be updated to “indicate” each item that was sent to a client, the claim
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does not require that the Bloom filter also indicate the identity of the client.
In other words, under the broadest reasonable interpretation of the claim, the
Bloom filter would reflect an item if it was “sent to a respective client,” but
the filter is not required to record which client the item was sent to.
Accordingly, in Van Vleet, when a plurality of users on a user account
request items (which are sent to them), the Bloom filter for that user ID is
updated to record each of those events. (See Van Vleet, fig. 2, col. 6 ll. 31-
45; see also id., col.4 ll. 7-9 (disclosing that multiple individuals may share a
user account).) We agree with Appellant that the Bloom filter in Van Vleet
would not be able to distinguish which of the multiple users requested each
item, but that is not required by claim 16.
Appellant further argues that Van Vleet is distinguishable because
each of the multiple users on the same user account also use the same client,
and claim 16 requires a plurality of clients. (App. Br. 27.) However, the
Examiner cited Figure 2 of Van Vleet, the description of which expressly
discloses that a single user account may be used on multiple clients such that
the associated Bloom filter would record the collective event data from all of
the clients used with that account’s user ID. (See Van Vleet, col. 6 ll.50-63.)
For the above reasons, the Examiner’s rejection of claims 16, 17, and
19-23 as being anticipated by Van Vleet is sustained.

Claims 12-15
With respect to claims 12-15, Appellant again argues that Van Vleet
does not anticipate the claims because it discloses only “user-specific”
Bloom filters that cannot distinguish between multiple users. (App. Br. 24-
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25, 32.) Independent claim 12 recites a “shared Bloom filter.” Unlike claim
1, however, claim 12 also recites a first and a second list of search results:
in response to search requests from each of a plurality of
users at respective clients, retrieving a list of results responsive
to each of the search request, including a first list of results
responsive to a first search request from a first user at a first
client and a second list of results responsive to a second search
request from a second user at a second client . . .
(emphases added). In particular, the recited “first user” and “second user”
are at different clients and have different search requests, which result in
different lists of results. Claim 12 further recites:
filtering results in the first list of results and results in the
second list of results with a shared Bloom filter to produce a
first filtered result list, comprising at least a portion of the first
list of results, and a second filtered result list, comprising at
least a portion of the second list of results;
sending the first filtered result list to the first client; and
sending the second filtered result list to the second client
(emphases added). Thus, the “shared” Bloom filter is applied to both lists of
results, producing one filtered result list for the first user and another filtered
result list for the second user, which are then sent to their respective clients.
The Examiner stated only that “Claim 12 is rejected based on the
rejection of claim 1 further in combination with multi users such as in Fig. 1
[of Van Vleet].” (Ans. 6; see also Ans. 8 (relying on findings with respect
to claim 1).) We agree with Appellant that the Examiner erred. In Van
Vleet, a Bloom filter may be applied to multiple users on the same user
account, as discussed supra. However, the Examiner has not identified any
disclosure in Van Vleet of a scenario where two users on the same account
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each send a search request from different clients, a Bloom filter is applied to
both sets of results, and each client is sent its own filtered result list.
Thus, based on the record before us, we do not sustain the rejection of
claim 12 as being anticipated by Van Vleet. Since claims 13-15 depend on
claim 12, we further do not sustain the rejection of claims 13-15 as being
anticipated by Van Vleet.

Claims 3, 18, and 26-28
Appellant separately argues the patentability of claims 3, 18, and 26-
28. However, the issues presented as to these claims are similar. Claim 3
recites “applying a plurality of hash functions to a value, which includes a
user identifier of the user and a content identifier . . .” (emphasis added).
Claim 18 recites “hashing a value comprising a combination of a plurality of
values, including an item identifier . . . and a user identifier . . .” (emphases
added). Claims 26-28 each recite “concatenating a user identifier with a
content identifier” and “applying the multi-user Bloom filter to the
concatenated results . . .” (emphasis added). Appellant asserts the Examiner
erred in finding that Van Vleet discloses these elements because the Bloom
filters and associated hash functions in Van Vleet are not applied to user
identifiers. (App. Br. 27-31.)
The Examiner found that Van Vleet discloses these disputed
limitations by describing the application of a Bloom filter’s hash functions to
an object URL, and explaining that accessed URLs are stored according to
user. (Ans. 8 (citing Van Vleet, col. 12 ll. 54-67, col. 13 ll. 25-28).) We
agree with Appellant that the Examiner’s finding is erroneous. Claims 3, 18,
and 26-28 require that hash functions (or Bloom filter) are applied to both a
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user identifier and a content identifier. Van Vleet discloses that only content
identifiers (e.g., URLs) are subject to the hash functions of the Bloom filter.
While the Bloom filters—and, thus, the hashed content identifiers—are
stored by user ID, the Examiner has not identified any disclosure in Van
Vleet of applying the Bloom filter (or any hash functions) to the user
identifier itself.
Therefore, we do not sustain the rejection of claims 3, 18, and 26-28
as being anticipated by Van Vleet.

DECISION
We affirm the Examiner’s rejection of claims 1, 2, 4-9, 11, 16, 17, and
19-25 as being unpatentable under 35 U.S.C. § 102(e).
We reverse the Examiner’s rejection of claims 3, 12-15, 18, and 26-28
as being unpatentable under 35 U.S.C. § 102(e).
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).

AFFIRMED-IN-PART

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