A PATENT MAY PROTECT A COMBINATION OF KNOWN ELEMENTS -
AS LONG AS THE COMBINATION IS NOT "OBVIOUS"
Akin, Gump, Strauss, Hauer & Feld, LLP
September 7, 1998
INTRODUCTION
An invention must meet certain minimum requirements to be protected by a U.S. patent. For example, to qualify for patent protection, an invention must be new and different from what has been known, used or described in the past. In addition, even if the invention is different from what has been known, used or described, a patent may not be obtained if the differences between the invention and the "prior art" are such that the invention, as a whole, would have been obvious to a person having ordinary skill in the art to which the invention relates. In other words, to achieve patent protection, not only must there be a difference between the invention and the prior art, but there must be a sufficient difference that the invention would not have been obvious to a person skilled in the area of technology related to the invention. The requirement that each patentable invention must be "nonobvious" is imposed by statute. The successful grant of a U.S. patent frequently depends upon the patent applicant's ability to persuade an examiner at the U.S. PTO that the subject invention is nonobvious. The issue of obviousness may also play a critical role in patent litigation, since a party accused of infringement may invalidate a U.S. patent by demonstrating that the invention protected by the patent is an obvious invention. In the recent case of In re Rouffet the U.S. Court of Appeals for the Federal Circuit ("the CAFC") had an opportunity to review the statutory requirement of nonobviousness and restate some of the principle tests used for evaluating nonobviousness. A detailed discussion of the Rouffet case and the CAFC's decision is provided below. This is followed by a description of some guidelines which should now be considered when assessing the obviousness (and consequently the patentability) of an invention.
THE INVENTION
The claimed invention in Rouffet was directed to a modern telecommunications system which used a network of satellites in low Earth orbit. These satellites projected a number of cone-shaped beams toward the Earth. Each beam transmitted to an area, or "footprint," on the Earth's surface. These footprints did not remain stationary, because the satellites moved relative to the Earth's surface. This relative motion meant that a receiver at a fixed location on the Earth's surface would "move" from the footprint of a beam transmitted by one satellite into the footprint of a beam transmitted by a second satellite. Each switch from one footprint to another created a "handover" event, similar to that which occurs when a cellular telephone travels from one cell to another. Handovers are undesirable because they can cause interruptions in signal transmission and reception. The invention sought to eliminate handover events caused by satellite motion. The invention achieved this by changing the shape of the beam transmitted by the satellites from a cone-shaped beam (which had a circular footprint) to a fan-shaped beam (which had an elliptical footprint). The long axis of the fan-shaped beam was aligned parallel to the direction of the satellite's motion across the Earth's surface. By elongating the beam's footprint in the direction of satellite travel, the invention ensured that a fixed point on the Earth's surface would tend to remain within a single footprint until it was necessary to switch to another satellite. Representative claim 1 recited:
A low orbit satellite communications system for mobile terminals, wherein the communications antenna system of each satellite provides isoflux coverage made up of a plurality of fan beams that are elongate in the travel direction of the satellite.
The PTO Board of Patent Appeals and Interferences (the Board) affirmed the rejection of claim 1 as being obvious over prior art reference "A" in view of prior art references "B" and "C". The applicant appealed this rejection to the CAFC.
THE APPEAL
The Requirement of Nonobviousness
On appeal, the CAFC noted that to reject a claim as obvious, an examiner must show an unrebutted prima facie case of obviousness. If a proper prima facie case of obviousness is not established, then an applicant complying with the other requirements of the patent statute is entitled to the grant of a patent. If a proper prima facie case of obviousness is established, then an applicant can overcome the obviousness rejection by: (1) showing that the evidence of prima facie obviousness is insufficient, or (2) rebutting the prima facie case of obviousness with evidence of secondary indicia of nonobviousness. The factual findings underlying an obviousness determination include: (1) the scope and content of the prior art, (2) the differences between the prior art and the claimed invention, and (3) the level of ordinary skill in the art. Another "essential component" of the obviousness determination is the objective or secondary indicia of nonobviousness. The objective evidence of nonobviousness may include: (1) copying of the invention, (2) long felt but unsolved need for the invention, (3) failure of others to achieve the invention, (4) commercial success of the invention, (5) unexpected results created by the invention, (6) unexpected properties of the invention, (7) licenses showing industry respect for the invention, and (8) skepticism of skilled persons prior to the invention. When an obviousness rejection depends on a combination of prior art references, there must be some teaching, suggestion, or motivation to combine the references. The suggestion to combine references may come from: (1) the nature of the problem addressed by the inventor, (2) the teachings of the relevant prior art references, or (3) the ordinary knowledge of those skilled in the art that certain references are of special importance in a particular field. Therefore, when determining the patentability of an invention which combines two known elements, the question is whether there is something in the prior art as a whole to suggest the desirability, and thus the obviousness, of making the combination. On appeal to the CAFC the ultimate determination of obviousness is reviewed as a question of law. An applicant may specifically challenge an obviousness rejection by showing that the Board: (1) reached an incorrect conclusion of obviousness, or (2) based its obviousness determination on incorrect facts. All of the applicant's evidence must be considered. The factual conclusions drawn from this evidence are reviewed for clear error. Whether the evidence presented is sufficient to rebut the prima facie case is part of the ultimate conclusion of obviousness, and is therefore a question of law.
An Invention May Include Known Elements
The Board had affirmed the rejection of claim 1 over the combination of references A, B and C. It was undisputed that the cited references were in the same field of endeavor as the invention, and that the level of skill in the art was high. The issue on appeal was therefore whether the Board had erred by improperly combining the cited references. Reference A disclosed a system for launching several satellites into low Earth orbit from a single launch vehicle. Reference B disclosed a geostationary satellite that used a plurality of fan-shaped beams with their longer axes oriented in an east-west direction to communicate with mobile and fixed terminals on the Earth. Reference C described a television broadcast system that used a series of satellites to retransmit signals sent from a ground station over a wide area. Rather than using a geostationary orbit, reference C disclosed the use of a series of satellites which always followed the same path through the sky when viewed from a fixed point on the ground. To transmit to these moving satellites from a ground station, reference C disclosed a fan beam with a long axis aligned with the long axis of the orbit's loop. This alignment placed the entire loop within the footprint of the beam and eliminated the need for a ground station antenna to track the satellite's motion around the loop. Reference C was different from the claimed invention in at least two respects: (1) reference C disclosed the projection of a single beam from the Earth to multiple satellites, whereas the claimed invention involved the projection of multiple beams from a satellite to the Earth; (2) to the extent that reference C disclosed anything about handovers, reference C disclosed the use of a unique orbit to ensure that a satellite always fell within the beam transmitted by the ground station. Although there were differences between the claimed invention and reference C, the Board found that the level of ordinary skill in the art was very high. Consequently, the Board found that a person of ordinary skill in the art would be able to account for the differences between the claimed invention and the prior art. In particular, a skilled person would know to shift the frame of reference from a ground station following a satellite (as in reference C) to a satellite transmitting to the ground (as in the claimed invention). The CAFC found no clear error in the Board's reliance on the high level of skill in the art to conclude that the differences between the claimed invention and the prior art would not prevent a finding of obviousness. Although reference C did not expressly disclose alignment of the fan beam with the apparent direction of the satellite's motion, the CAFC found no clear error in the Board's determination that reference C would suggest such an alignment to a skilled person. The CAFC therefore concluded that the Board had not erred in finding that the combination of references A, B and C disclosed all of the elements recited in claim 1.
A Suggestion to Combine Known Elements is Critical
However, the CAFC did find reversible error in the Board's failure to identify any motivation to select references A, B and C for combination. The CAFC noted that reference C did not specifically discuss handover minimization. To the extent that reference C discussed handovers, the reference discussed the selection of orbital parameters, not the choice of a particular shape and alignment of the beam projected by the satellite. According to the CAFC, the Board failed to provide any reason why a skilled person, seeking to minimize handovers due to satellite motion, would combine reference C with references A and B in a manner that would make the claimed invention obvious. The CAFC observed that virtually all inventions are combinations of old elements. Consequently, it is often the case that every element of an invention may be found in the prior art. If patentability could be refused merely by demonstrating that each element of an invention is found in the prior art, then very few patents would be granted. Furthermore, if patents could be rejected by merely identifying each claim element that is found in the prior art, then examiners would use the claimed invention itself as a guide for piecing together elements in the prior art to defeat the patentability of the claimed invention. The CAFC noted that such an approach to determining patentability would be illogical and inappropriate. To prevent the use of hindsight based on the invention to defeat patentability of the invention, an examiner must show a motivation to combine the references that create the case of obviousness. In other words, an examiner must show a reason why a skilled person, confronted with the same problem as the inventor and with no knowledge of the claimed invention, would select the elements from the cited prior art references for combination in the manner claimed. The requirement that an examiner must show a "suggestion to combine" is a safeguard against the use of hindsight combinations to prevent patentability. The CAFC identified three possible sources for a motivation to combine references: (1) the nature of the problem to be solved, (2) the teachings of the prior art, and (3) the knowledge of persons of ordinary skill in the art. In Rouffet the Board had relied upon none of these. Rather, the Board had relied on the high level of skill in the art to provide the necessary motivation (just as the Board had relied on the high level of skill in the art to overcome the differences between the claimed invention and the references). The Board did not, however, explain what specific understanding or technological principle within the knowledge of a skilled person would have suggested the combination. The CAFC explained that a high level of skill in the art is not sufficient to overcome the absence of an actual suggestion that one could select part of the teachings for combination. While the level of skill in the art is one part of the inquiry for a suggestion to combine, a high level of skill alone is not sufficient to supply a motivation to combine. If a high level of skill in the art was alone sufficient to supply a motivation to combine, then there would be very few patentable inventions in the more sophisticated scientific fields. Instead, in complex scientific fields, the PTO could routinely identify the prior art elements in an application, observe that there was a high level of skill in the art, and simply reject the claims on that basis. A high level of skill in an art would thereby almost always prevent patentable inventions. The CAFC stated that invention may be characterized as the process of combining prior art in a nonobvious manner. Therefore, even when the level of skill in the art is high, the PTO must specifically identify the principle, known to a skilled person, that suggests the claimed combination. In other words, the PTO must explain the reasons why a skilled person would have been motivated to select the references and to combine them to render the claimed invention obvious. According to the CAFC, the requirement that there must be a suggestion to combine references is a critical safeguard against hindsight analysis and rote application of the legal test for obviousness. The Board had failed to explain the specific understanding or principle within the knowledge of a skilled person that would motivate one with no knowledge of the invention to make the combination. The CAFC found that the Board's exclusive reliance on a high level of skill in the art to supply a suggestion to combine the cited references was clearly erroneous. Absent any proper motivation to combine, the rejection of the claim over these references was improper and was reversed by the CAFC.
Those who seek to obtain and enforce a U.S. patent, as well as those who seek to to avoid liability for alleged patent infringement, are well advised to study the Rouffet case and carefully consider the following guidelines regarding the obviousness (and consequently the patentability) of an invention:
(1) Almost all inventions are combinations of known elements. Every element of an invention may usually be found in the prior art. Consequently, patentability can not be refused merely by demonstrating that each element of an invention is found in the prior art.
(2) A high level of skill in the art may alone be sufficient to overcome the differences between the invention and the prior art references. However, a high level of skill in the art is not alone sufficient to supply a motivation or suggestion to combine the prior art references.
(3) Even when the level of skill in the art is very high, the PTO must still explain the reasons why a skilled person would have been motivated to select the prior art references and to combine them in a manner which renders the claimed invention obvious. The suggestion to combine references may come from: (1) the nature of the problem addressed by the inventor, (2) the teachings of the relevant prior art references, or (3) the
ordinary knowledge of skilled persons that certain references are of special importance in a particular field. The requirement that there must be a suggestion to combine references is a critical safeguard against hindsight analysis and rote application of the legal test for obviousness.
Consideration of the guidelines suggested by the CAFC in the Rouffet decision and
expressed in this article should provide some useful insights into the U.S. patent law
requirement of nonobviousness.
BIOGRAPHY
Alex Chartove practices in the Washington D.C. office of Akin, Gump, Strauss,
Hauer & Feld, LLP (http://www.akingump.com), a full-service international law firm with
offices in the U.S. and Europe. Mr. Chartove attended Brandeis University (BA, Physics,
magna cum laude, 1976) and the Massachusetts Institute of Technology (Ph.D.
Candidate). He received his JD degree in 1980 from Duke University Law School, and is
a member of the Bars of California, New York and the District of Columbia. His practice
is directed to the representation of client matters before the various federal tribunals and
agencies located in Washington D.C., including the U.S. Patent and Trademark Office, the
Court of Appeals for the Federal Circuit, the International Trade Commission and the
Copyright Office. For the past five years, Mr. Chartove has been the author of the "Federal Circuit Yearbook", published by the Practising Law Institute (http://www.pli.edu). Mr. Chartove's "Yearbook" provides a comprehensive summary and analysis of every patent law decision published by the CAFC during the past year. E-mail: achartove@akingump.com.
COPYRIGHT 1998, Akin, Gump, Strauss, Hauer & Feld, L.L.P. All rights reserved.
