■ Anitа Dembiezak and Benson Zinbarg appeal the rejection, upheld by the Board of Patent Appeals and Interferences, of all pending claims in their Application No. 08/427,732. See Ex Parte Dembiczak, No. 96-2648, slip op. at 43 (May 14, 1998). Because the Board erred in sustaining rejections of the pending claims as obvious under 35 U.S.C. § 103(a) (Supp.1998), and for obviousness-type double patenting, we reverse.
I
The invention at issue in this case is; generally speaking, a large trash bag made of orange plastic and decorated with lines and facial features, allowing the bag, when filled with trash or leaves, to resemble a Halloween-style pumpkin, or jack-o’-lantern. As the inventors, Anita Dembiezak and Benson Zinbarg (collectively, “Dem-biezak”) note, the invention solves the long-standing problem of unsightly trash bags placed on the curbs of America, and, by fortuitous happenstance, allows users to express their whimsical or festive nature while properly storing garbage, leaves, or other housеhold debris awaiting collection. Embodiments of the invention — sold under a variety of names, including Giant Stuff-A-Pumpkin, Funkins, Jack Sak, and Bag-O-Fun — have undisputedly been well-received by consumers, who bought more than seven million units in 1990 alone. Indeed, in 1990, the popularity of the pumpkin bags engendered a rash of thefts around Houston, Texas, leading some owners to resort to preventative measures, such as greasing the bags with petroleum jelly and tying them to trees. See R. Piller, “Halloween Hopes Die on the Vine,” Hous. Chron., Oct. 19,1990, at 13A.
The road to profits has proved much еasier than the path to patentability, however. In July 1989, Dembiezak filed a utility patent application generally directed to the pumpkin bags. In a February 1992 appeal, the Board of Patent Appeals and Interferences (“the Board”) reversed the Examiner’s rejection, but entered new grounds for rejection. Dembiezak elected to continue prosecution, filing a continuation application to address the new grounds for rejection. Thereaftеr, the invention made a second appearance before the Board, in April 1993, when the Board both sustained the Examiner’s rejection and again entered new grounds for rejection. Again, a continuation application was filed (the instant application). And again the Examiner’s rejection was appealed to the Board, which sustained the rejection in a May 14, 1998, decision. See Dembiezak, slip op. at 43.
A
The patent application at issue includes claims directed to various embodiments of *997 the pumpkin bag. Claims 37, 49, 51, 52, 58 through 64, 66 through 69, and 72 through 81 are at issue in this appeal. Though the claims vary, independent claim 74 is perhaps most representative:
74. A decorative bag for use by a user with trash filling material, the bag simulating the general outer appearance of an outer surface of a pumpkin having facial indicia thereon, comprising:
a flexible waterproof plastic trash or leaf bag having
an outer surface which is premanufac-tured orange in color for the user to simulate the general appearance of the outer skin of a pumpkin, and having
facial indicia including at least two of an eye, a nose and a mouth on the orange color outer surface for forming a face pattern on said orange color outer surface to simulate the general outer appearance of a decorative pumpkin with a face thereon,
said trash or leaf bag having first and second opposite ends, at least said seсond end having an opening extending substantially across the full width of said trash or leaf bag for receiving the trash filling material,
wherein when said trash or leaf bag is filled with trash filling material and closed, said trash or leaf bag takes the form and general appearance of a pumpkin with a face thereon.
All of the independent claims on appeal, namely 37, 52, 72, and 74, contain limitations that the bag must be “premanufac-tured orange in color,” have “facial indi-cia,” have openings suitable for filling with trash material, and that when filled, the bag must have a generally rounded appearance, like a pumpkin. Independent claims 37, 52, and 72 add the limitation that the bag’s height must at least 36 inches. Claim 72 requires that the bag be made of a “weatherproof material,” and claim 74, as shown above, requires that the bag be “waterproof.” Claim 52 recites a “method of assembling” a bag with the general characteristics of apparatus claim 37.
B
The prior art cited by the Board includes:
(1) pаges 24-25 of a book entitled “A Handbook for Teachers of Elementary Art,” by Holiday Art Activities (“Holiday”), describing how to teach children to make a “Crepe Paper Jack-O-Lantern” out of a strip of orange crepe paper, construction paper cut-outs in the shape of facial features, and “wadded newspapers” as filling;
(2) page 73 of a book entitled “The Everything Book for Teachers of Young Children,” by Martha Shapiro and Valerie Indenbaum (“Shapiro”), describing a method of making a “paper bag pumpkin” by stuffing a bag with newspapers, painting it orange, and then painting on facial features with black paint;
(3) U.S. Patent No. 3,349,991 to Leonard Kessler, entitled “Flexible Container” (“Kessler”), describing a bag apparatus wherein the bag closure is accomplished by the use of folds or gussets in the bag material;
(4) U.S. Patent No. Des. 310,023, issued August 21, 1990 to Dembiczak (“Dembiczak ’023”), a design patent depicting a bag with a jack-o’-lantern face;
(5) U.S. Patent No. Des. 317,254, issued June 4, 1991 to Dembiczak (“Dem-biczak ’254”), a design patent depicting a bag with a jack-o’-lantern face; and,
(6) Prior art “conventional” plastic lawn or trash bags (“the conventional trash bags”).
Using this art, the Board affirmed the Examiner’s final rejection of all the independent claims (37, 52, 72, 74) under 35 *998 U.S.C. § 103, holding that they would have been obvious in light of the conventional trash bags in view of the Holiday and Shapiro references. The Board determined that, in its view of the prior art, “the only difference between the invention presently defined in the independent claims on appeal and the orange plastic trash bags of the prior art and the use of such bags resides in the application of the facial indicia to the outer surface of the bag.” Dembiczak, slip op. at 18. The Board further held that the missing facial indicia elements were provided by the Holiday and Shapiro references’ description of painting jack-o’-lantern faces on paper bаgs. See id. at 18-19. Dependent claims 49 and 79, which include a “gussets” limitation, were considered obvious under similar reasoning, except that the references cited against them included Kessler. See id. at 7.
The Board also affirmed the Examiner’s obviousness-type double patenting rejection of all the independent claims in light of the two Dembiczak design patents (’023 and ’254) and Holiday. See id. at 12. The Board held that the design patents depict a generally rounded bag with jack-o’-lantern facial indicia, and thаt the Holiday reference supplies the missing limitations, such as the “thin, flexible material” of manufacture, the orange color, the initially-open upper end, and the trash filling material. The Board also stated that the various limitations of the dependent claims — e.g., color, the inclusion of leaves as stuffing, and the dimensions — would all be obvious variations of the depictions in the Dembiczak design patents. See id. at 8-9. In addition, using a two-way test for obviousness-type double patenting, the Board hеld that the claims of the Dembic-zak design patents “do not exclude” the additional structural limitations of the pending utility claims, and thus the design patents were merely obvious variations of the subject matter disclosed in the utility claims. See id. at 11. The Board further upheld, on similar grounds and with the inclusion of the Kessler reference, the obviousness-type double patenting rejection of dependent claim 49. See id. at 12.
This appeal followed, vesting this court with jurisdiction pursuant to 28 U.S.C. § 1295(a)(4)(A) (1994).
II
A claimed invention is unpatentable if the differences between it and the prior art “are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art.” 35 U.S.C. § 103(a) (Supp.1998);
see Graham v. John Deere Co.,
A
Our analysis begins in the text of section 103 quoted above, with the phrase “at the time the invention was made.” For it is this phrase that guards against entry into the “tempting but forbidden zone of hindsight,”
see Loctite Corp. v. Ultraseal Ltd.,
Our case law makes clear that the best defense against the subtle but powerful attraction of a hindsight-based obviousness analysis is rigorous application of the requirement for a showing of the teaching or motivation to combine prior art references.
See,
e.g.,
C.R. Bard, Inc. v. M3 Sys., Inc.,
We have noted that evidence of a suggestion, teaching, or motivation to combine may flow from the prior art references themselves, the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved,
see Pro-Mold & Tool Co. v. Great Lakes Plastics, Inc.,
All the obviousness rejections affirmed by the Board resulted from a combination of prior art references, e.g., the conventiоnal trash or yard bags, and the Holiday and Shapiro publications teaching the construction of decorated paper bags. See Dembiczak, slip op. at 6-7. To justify this combination, the Board simply stated that “the Holiday and Shapiro references would have suggested the application of ... facial indicia to the prior art plastic trash bags.” Id. at 18-19. However, rather than pointing to specific information in Holiday or Shapiro that suggest the combination with the conventional bags, the Board instead described in detail the similarities between the Holiday and Shapiro references and the claimed invention, noting that one reference or the other — in combination with each other and the conventional trash bags — described all of the limitations of the pending claims. See id. at 18-28. Nowhere does the Board particularly identify any suggestion, teaching, or motivation to combine the children’s art references (Holiday and Shapiro) with the conventional trash or lawn bag references, nor does the Board make specific — or even inferential — findings concerning the identification of the relevant art, the level of ordinary skill in the art, the nature of the problem to be solved, or any other factual findings that might serve to support a proper obviousness analysis. See, e.g., Pro-Mold & Tool, 75 F.3d at 1573, 37 USPQ2d at 1630.
To the contrary, the obviousness analysis in the Board’s decision is limited to a discussion of the ways that the multiple prior art references can bе combined to read on the claimed invention. For example, the Board finds that the Holiday bag reference depicts a “premanufactured orange” bag material, see
Dembiczak,
slip op. at 21, finds that Shapiro teaches the use of paper bags in various sizes, including “large”, see
id.
at 22-23, and concludes that the substitution of orange plastic for the crepe paper of Holiday and the paper bags of Shapiro would be an obvious design choice, see
id.
at 24. Yet this reference-by-reference, limitation-by-limitation analysis fails to demonstrate how the Holiday and Shapiro references teach or suggest their combination with the conventional trash or lawn bags to yield the claimed invention.
See Rouffet,
B
The Commissioner of Patents and Trademarks (“Commissioner”) attempts to justify the Board’s decision on grounds
*1001
different from that relied upon by the Board, arguing that one of ordinary skill in the art would have been motivated to combine the references. Of course, in order to do so, the Commissionеr must do what the Board did not do below: make specific findings of fact regarding the level of skill in the art (“a designer and manufacturer of trash and leaf bags, particularly one specializing in the ornamental and graphic design of such bags”), Resp’t Br. at 14, the relationship between the fields of conventional trash bags and children’s crafts, respectively (“[t]he artisan would also have been well aware of the ancillary, corollary, and atypical uses of ‘trash’ bags such аs their application in hobby and art projects”), Resp’t Br. at 15, and the particular features of the prior art references that would motivate one of ordinary skill in a particular art to select elements disclosed in references from a wholly different field (“a designer and manufacturer of trash and leaf bags would have recognized the paper bag in Shapiro to be a trash bag and therefore would have been motivated to combine it with the admittеd prior art plastic trash and leaf bags to arrive at the claimed invention”), Resp’t Br. at 15. The Commissioner also appears to cite additional references in support of his obviousness analysis, noting that at least two design patents (in the record but not cited against the presently pending claims) teach the placement of “graphical information, including text, designs, and even facial indicia, to colored bags.” Resp’t Br. at 16. This new analysis, apparently cut from whole cloth in view of appeal, does little more than highlight the shortcomings of the decision below, and we decline to consider it.
See;
e.g.,
In re Robertson,
Ill
Dembiczak also asks this court to reverse the Board’s rejection of the pending claims for obviousness-type double patenting, which is a judicially-created doctrine that seeks to prevent the applicant from expanding the grant of the patent right beyond the limits prescribed in Title 35.
See,
e.g.,
In re Braat,
*1002 A
The law provides that, in some very rare cases, obvious-type double patenting may be found between design and utility patents.
See Carman Indus., Inc. v. Wahl,
B
In making its double patenting rejection, the Board concluded that all but one of the pending claims of Dembiczak’s utility application would have been merely an obvious variation of the claims of the earlier-issued design patents — the Dembiczak ’023 and ’254 references — in light of the Holiday reference. The remaining claim, dependent claim 49, was judged obvious in light of the combination of the Dembiczak design patents, Holiday, and the Kessler reference.
Acknowledging that the two-way test was required by
Carman,
Because we find that the Board erred in concluding that the design patents were obvious variants of the pending utility claims, we need not address the other prong of the two-way double patenting test — whether the pending utility claims are obvious variations of the subject matter claimed in the design patents.
See Carman,
IV
Because there is no evidence in the record of a suggestion, teaching, or motivation to combine the prior art references asserted against the pending claims, the obviousness rejections are reversed. In addition, because the Board misapprehended the test for obviousness-type double patenting, and because the pending utility claims do not render obvious the design patents, the double patenting rejections are also reversed.
REVERSED.