Ching-Rong Wang - (“Wang”) appeals from the judgment of the United States District Court for the District of Columbia, overturning the decision of the United States Patent and Trademark Office Board of Patent Appeals and Interferences (the “Board”) in an interference, and holding that the inventions of claims 2 and 4 of U.S. Patent No. 4,935,047 (“the ’047 patent”) and claims 9-11 of U.S. Patent App. No. 07/478,411 (“the ’411 application”) would not have been obvious in light of the cited prior art.
See Winner Int’l Royalty Corp. v. Wang,
BACKGROUND
In addition to the ’047 patent, Winner also owns U.S. Patent No. 4,738,127 (“Johnson”), the commercial embodiment of which is the original steering wheel anti-theft device known as “The Club.” Wu, the principal in the Taiwanese manufacturer of the original Club, is named as the inventor in the ’047 patent, commercial embodiments of which are known as “The Super Club,” “The Ultra Club,” and “The Club, GL.” The ’047 patent discloses an automo *1343 bile anti-theft device that is mounted across the steering wheel and is locked in place by use of a self-locking ratcheting mechanism. Like all versions of the Club, when locked in place, the commercial embodiments of the ’047 patent prevent theft by blocking the steering wheel from turning. The ratcheting mechanism is different from the dead-bolt used in Johnson and so the ’047 patent may be thought of as an improvement over Johnson. While Johnson’s dead-bolt system is more secure, it is not as convenient as the ratcheting mechanism claimed in the ’047 patent because a key is required to lock the Johnson device in place while the ’047 patent discloses a device that locks itself without use of a key. 1
Wang also manufactures similar anti-theft devices in Taiwan and exports them to the U.S. where he sells them through his United States distributor. Wang’s device is known commercially as “The Gorilla Grip.” Wang filed a patent application directed to his Gorilla Grip device and was issued U.S. Patent No. 4,887,443 (“the ’443 patent”).
In 1990, Wu discovered that the device disclosed in Wang’s ’443 patent was very similar to the subject matter of his then-pending application, which later issued as the ’047 patent, and decided to provoke an interference by filing a divisional application and submitting a claim identical to the broadest claim in the ’443 patent. On August 8, 1991, an interference was declared, and a proceeding began to determine which party, Wu or Wang, had priority of invention. The claims of the ’047 patent and an additional Wu application, the ’411 application, were eventually added to the count in the interference.
During the interference proceeding, Wang filed a preliminary motion alleging that the interference count, and hence both parties’ claims, was unpatentable as obvious in light of certain prior art under 35 U.S.C. § 103 (1994). Wang, apparently acknowledging that his claim to priority over Wu’s ’047 patent was questionable, ultimately conceded that his ’443 patent was invalid and sought to prove that Wu’s ’047 patent was also invalid.
After a final hearing, the Board, in a split decision, held all affected claims invalid except for claims 1 and 3 of the ’047 patent. Wu then filed both an appeal to this court pursuant to 35 U.S.C. § 141 (1994) and an action in the District Court for the District of Columbia pursuant to 35 U.S.C. § 146, while Wang filed a section 146 action in the District Court for the Central District of California. In Wu’s section 141 appeal from the decision of the Board, this court determined that the section 146 suit would proceed pursuant to Wu’s complaint in the District Court for the District of Columbia.
See Wu v. Wang,
After the first appeal to this court, Wang filed a motion in the district court to transfer the action to the Central District of California. The district court denied the motion.
See Winner,
45 USPQ2d 1864. After a seven-day bench trial, the district court held that the inventions of claims 2 and 4 of the ’047 patent would not have been obvious in light of the cited prior art.
See Winner,
The focus of the trial was on four prior art references that Wang alleged, before the court as he had before the Board, rendered the invention of the ’047 patent obvious. These references were Johnson (mentioned above), U.S. Patent No. 3,462,-982 (“Moore”), Taiwan Patent App. No. 74,210,699 CWuROC”), and French Patent App. No. 2,566,398 (“Grimaldi”). Winner also introduced evidence of the commercial success of its Super Club line of products. This evidence had not been presented to the Board.
Like the device disclosed in the ’047 patent, the mechanism of Johnson immobilizes the steering wheel by the user inserting it within the steering wheel, telescoping its arms outward so that hooks on the end of the arms engage the steering wheel, and then locking the arms in place. As stated earlier, unlike the ’047 patent, which discloses a self-locking ratcheting mechanism, Johnson uses a dead-bolt to lock the device in place, which requires the user to turn a key after putting the device on the wheel. Moore discloses a steering wheel lock that unfolds into a “Y” shape and utilizes a self-locking ratcheting mechanism, which does not require a key. WuR-OC discloses a wheel and brake pedal locking device with a versatile locking core that can accommodate either a dead-bolt or a self-locking ratcheting mechanism, but it does not disclose either of these locking mechanisms. Grimaldi discloses a two-piece mechanism for locking a clutch or brake pedal to the floorboard or firewall of a car and its figures appear to show a rod and pawl mechanism that locks it into place.
The key issue tried was the presence or absence of sufficient proof of a motivation to combine the four prior art references. The Board had found that one skilled in the art (1) “would have considered Johnson’s dead-bolt-type locking device to be disadvantageous compared to the Moore and WuROC devices to the extent that Johnson requires a key for setting in position and adjusting the device,” and (2) “would have been motivated to make Johnson easier to use, albeit less secure, by replacing the dead-bolt mechanism” of Johnson with a suitable self-locking ratcheting mechanism. The district court found that these factual findings were “clearly erroneous” and found that adequate motivation to combine the references was not shown.
See Winner,
Wang appeals, contending that the district court should have applied a substantial evidence standard of review on factual issues rather than, as it said it was doing, review for clear error. Wang asserts that the district court incorrectly concluded that the invention of the claims would not have been obvious, and abused its discretion in admitting the challenged documentary evidence and testimony as duplicative of evidence in the Board record and in denying Wang’s motion to transfer the case to the Central District of California. We have jurisdiction pursuant to 28 U.S.C. § 1295(a)(3)(C) (1994).
DISCUSSION
I.
STANDARD OF REVIEW
We review the district court’s factual findings for clear error and its
*1345
conclusions of law
de novo,
as with any bench trial.
See Gould v. Quigg,
Wu brought this action pursuant to 35 U.S.C. § 146, which allows a party to an interference dissatisfied with an adverse decision of the Board to file a complaint in a district court. Unlike a direct appeal to this court pursuant to 35 U.S.C. § 141, the parties before the district court are not limited to the evidentiary record before the Board:
In such suits the record in the Patent and Trademark Office shall be admitted on motion of either party ... without prejudice to the right of the parties to take further testimony. The testimony and exhibits of the record in the Patent and Trademark Office when admitted shall have the same effect as if originally taken and produced in the suit.
35 U.S.C. § 146 (emphasis added). Because the record before the district court may include the evidence before the Board as well as evidence that was not before the Board, we have often described the district court proceeding as “a hybrid of an appeal and a trial
de novo.” Estee Lauder Inc. v. L’Oreal, S.A.,
The issue before us is whether the scope of the evidence admitted by the district court was sufficient to require a complete trial
de novo,
or whether the district court was instead required to give deference to some or all of the Board’s findings of fact. Although our precedent makes clear that a
de novo
trial is appropriate in some circumstances in actions under both section 146 and the parallel provisions in 35 U.S.C. § 145, it does not make clear exactly what those circumstances are. The statutory provisions themselves offer little guidance — section 146 only refers to “further testimony” which may be offered in the district court, while section 145 is completely silent about evidence.
See
35 U.S.C. § 146; 35 U.S.C. § 145. In
Zurko,
the Supreme Court, in passing, noted the settled law that in a section 145 action a disappointed applicant may present evi
*1346
dence that it did not present to the Board, and that the “presence of such
new
or
different
evidence makes a factfinder of the district judge.”
Here, Winner introduced evidence on the issue of commercial success that was not before the Board, specifically a survey and a witness. Such documentary evidence and testimony are certainly “further testimony,” as the Board had neither before it in any form. However, Winner also presented live testimony in the district court on each factual issue before the Board, namely the other three sets of underlying factual determinations typically at issue in an obviousness determination.
See Graham v. John Deere Co.,
In the context of a section 145 action, in which the Board has conducted an
ex parte
proceeding, we have noted that the admission of live testimony at trial requires the factfinder to make
its own
findings.
See Burlington Indus., Inc. v. Quigg,
In its evaluation of the evidence on which this conclusion was based, the district court had a powerful advantage over the patent examiner and the Board, an advantage characteristic of section 145 appeals, in that the court heard and saw witnesses, testifying under examination and cross-examination, and had the benefit of extensive discussion and argument.
Id. at 1582, 3 USPQ2d at 1437-38 (emphasis added). The fact that the district court heard live testimony, gave more weight to some witnesses than to others, and came to a different conclusion than that reached by the Board, was not improper:
This trial before the district court partook of the quality that is available only with the examination and cross-examination of live witnesses. ... If the evidence adduced before the district court led to a decision different from that reached by the PTO, that is not contrary to the legislative purpose of section 145 de novo review. Indeed, it is in fulfillment of that purpose.
Id.
at 1584, 3 USPQ2d at 1439 (emphasis added). Thus, after a “full trial of the issues” the district court was free to come
*1347
to its own “independent conclusion,” contrary to the argument by the Commissioner.
Id.; see also Gould,
In the context of a section 146 action such as the instant case, in which the Board has conducted an
inter partes
interference proceeding, the matter is less clear because more evidentiary opportunities are available to parties in an interference than to an applicant in an
ex parte
examination and appeal to the Board.
See In re Epstein,
We hold that the admission of live testimony on all matters before the Board in a section 146 action, as in this case, makes a factfinder of the district court and requires a de novo trial. 4 Thus, although the live testimony before the district court might be the same or similar to testimony before the Board in the form of affidavits and deposition transcripts, a district court should still make de novo factual findings, while treating the record before the Board when offered by a party “as if [it was] originally taken and produced” in the district court. 35 U.S.C. § 146. Accordingly, because Winner submitted live testimony on all matters before the Board, the entire district court proceeding should have been a trial de novo, based both on the Board record and the district court evidence. 5
Our holding comports with the notion that “[t]he credibility of the witnesses and the weight to be given to their testimony and the other evidence in the record ... is a matter for the trier of facts.”
Gyromat Corp. v. Champion Spark Plug Co.,
II.
OBVIOUSNESS
A.
Obviousness is a question of law based on underlying factual inquiries including: (1) the scope and content of the prior art; (2) the level of ordinary skill in the art; (3) the differences between the prior art and the claimed invention; and (4) extent of any objective indicia of non-obviousness.
See Monarch Knitting Mach. Corp. v. Sulzer Morat Gmbh,
The dispute here focuses on the combinability of the prior art. When an obviousness determination is based on multiple prior art references, there must be a showing of some “teaching, suggestion, or reason” to combine the references.
Gambro Lundia AB v. Baxter Healthcare Corp.,
Evidence of a suggestion, teaching, or motivation to combine prior art references may flow,
inter alia,
from the references themselves, the knowledge of one of ordinary skill in the art, or from the nature of the problem to be solved.
See Dembiczak,
B.
Like the district court’s opinion, the arguments of both parties on appeal focus on whether one of ordinary skill would have been motivated to combine the four references. The key references at issue were Johnson, which discloses virtually all aspects of the invention claimed in the ’047 patent except ratcheting, and Moore, which did disclose a self-locking ratcheting mechanism.
7
If there was no motivation or suggestion to combine Johnson with the ratcheting mechanism of Moore, one of ordinary skill in the art would not have viewed the invention of the ’047 patent as obvious.
See In re Dance,
Wang argues that the prior art should be combinable merely because the Board properly found that the relevant field was very broad and included lock design art in general, and all of the prior art here was clearly within that field. Wang further argues that Moore is combinable with Johnson because they both deal with locking steering wheels, even though Moore’s ratcheting mechanism is possibly not as strong or as tamper resistant as the deadbolt mechanism of Johnson, partly because the grooves of the ratcheting mechanism are at least somewhat exposed.
The district court found that there was no motivation to combine Johnson with the ratcheting mechanism of Moore because (1) there was no apparent disadvantage to the dead-bolt mechanism of Johnson, and therefore the motivation to combine would not stem from the “nature of the problem” facing one of ordinary skill in the art, because no “problem” was perceived; and (2) Johnson’s written description taught away from the use of Moore.
See Winner,
First, although there was conflicting evidence before the district court on whether one would see the trade-off between using a dead-bolt and using a ratcheting mechanism and conclude that the more secure dead-bolt should be replaced with the more convenient ratcheting mechanism, the district court did not clearly err in finding that one of ordinary skill in the art would not have reasonably elected trading the benefit of security for that of convenience. Trade-offs often concern what is feasible, not what is, on balance, desirable. Motivation to combine requires the latter. 8
Second, if Johnson did in fact teach away from Moore, then that finding
*1350
alone can defeat Wang’s obviousness claim.
See Gambro Lundia AB,
The passage of Johnson relied on by the district court and Winner includes the following:
Another problem with such devices is that they appear susceptible to being overcome by physical force or manipulation. The locking mechanisms of [Moore] and Mitchell et al U.S. Pat. No. 4,103,524 are exposed, and include pry points thereabout in which a crowbar may be inserted in an attempt to overcome such mechanism. Irrespective of whether such device can be overcome by physical manipulation, they present prospective thieves with the appearance of being breakable.
Johnson, col. 1, lines 38-48. Because the Mitchell reference cited in the quote above actually does
not
utilize a ratcheting mechanism, Wang argues that Johnson does not teach away from using ratcheting mechanisms; rather, it was merely distinguishing prior art devices on the basis that unlike Johnson they had
exposed
mechanisms. However, that fact does not undermine the district court’s finding that Johnson did teach away from the ratcheting mechanism of Moore which does have exposed grooves. While we regard this as a close factual issue, we hold that the district court did not clearly err in finding that Johnson taught away from Moore, and therefore was not shown to be combinable with Moore. Because the district court did not clearly err in finding that one of ordinary skill would not be motivated to combine Johnson and Moore, the district court correctly concluded that Wang did not establish a prima facie case of obviousness by clear and convincing evidence.
See In re Dance,
If Wang had succeeded in establishing a prima facie case of obviousness based on the first three obviousness factors, the burden of production would have shifted to Winner.
See In re Huang,
Assuming,
arguendo,
prima facie proof of obviousness, we do not believe the district court clearly erred in finding commercial success or that it erred in concluding that it overcame the other
Graham
factors. It is presumed that Winner established a nexus between its commercial sales of the Super Club, the Club GL and Ultra Club and the patented features because they embody the disclosure of the ’047 improvement patent.
J.T. Eaton & Co. v. Atlantic Paste & Glue Co.,
III.
EVIDENTIARY ISSUES
A district court’s decision to admit or exclude evidence at trial is reviewed for abuse of discretion.
See Conservolite,
Winner points out that Wang never even identifies which witnesses should not have been allowed to testify as “late-disclosed.” With respect to the evidence of commercial success, Winner argues that the nexus evidence was clearly admissible because commercial success was at issue before the Board and, therefore by implication, the nexus issue was as well.
We agree with Winner that the district court did not abuse its discretion in allowing allegedly late-disclosed witnesses to testify. Such witnesses were never even identified by Wang in his opening brief, and, after Winner pointed this out in its response brief, Wang still failed to identify the witnesses in his reply brief. Under such circumstances, we will not search the record on the chance of discovering which witnesses Wang was complaining of and then determine whether the district court abused its discretion. Thus, whichever witnesses Wang was alluding to, admission of their testimony cannot be said to be an abuse of discretion based on the vague arguments made by Wang on appeal.
We also agree with Winner that the district court did not abuse its discretion in admitting the new testimony and survey report regarding the nexus between commercial success and the pat-entably distinct feature of the claimed invention. Wang’s argument, based on a distinction between the issues of commercial success and nexus, is flawed. The evidence showing a nexus between large sales and the patentable features of the invention of the ’047 improvement patent is at least
relevant to
the issue of commercial success before the Board.
See Estee Lauder,
IV.
MOTION TO TRANSFER
A district court may transfer an action to another district court for the “convenience of parties and witnesses, in the interest of justice.” 28 U.S.C. § 1404(a) (1994). Our review of the district court’s denial of Wang’s motion to transfer, as a procedural matter, is governed by the law of the regional circuit in which it sits, here the United States Court of Appeals for the District of Columbia Circuit.
See Stewart Org., Inc. v. Ricoh Corp.,
Wang argues that the district court should have granted his motion to transfer this action to the District Court for the Central District of California, where several other cases have been stayed pending the outcome of the interference and this action because to do so would be convenient to the parties and in the interests of justice. Winner argues, however, that it was just as convenient for the parties to litigate in Washington, D.C. as in California, and that the interests of justice actually favored litigation in Washington, D.C. because this aspect of the litigation will be resolved years before it would have been if the motion to transfer were granted.
We discern no abuse of discretion in the district court’s denial of Wang’s motion to transfer. Even though there are several related pending cases in the Central District of California, it is not clear that it would be a more convenient location for the parties to litigate. Persons scheduled to testify at trial for the parties lived in Pennsylvania; the experts lived in Connecticut, Virginia, and California; and the attorneys were from Virginia and New York. With parties, witnesses, and attorneys coming from such varied locations, several of which are closer to Washington, D.C. than California, it could not easily be said that it would be more convenient to try the case in the Central District of California. ,In addition, the interests of judicial economy were well served because the section 146 action was tried and result obtained in just six months after the motion to transfer was denied — presumably much more quickly than would have been the case if this action were transferred to the Central District of California where several other cases were pending.
See Savoy Indus.,
V.
CONCLUSION
The district court did not clearly err in its findings of fact with respect to its obviousness analysis and did not err in concluding that the invention of the ’047 patent would not have been obvious. In addition, the district court did not abuse its discretion in admitting testimony and documents or in refusing to transfer the *1353 case. Accordingly, the judgment of the district court is
AFFIRMED.
Notes
. In both devices a key is needed to unlock the device.
. The related claims in the '411 application were also found not unpatentable, but were not separately addressed by the- district court and are not separately argued on appeal. Therefore, we do not address them separately either.
. That standard of review was correct under our case law at the time.
. As this case involved further testimony relating to everything in issue before the Board, we express no opinion on whether testimony relating solely to some facts or issues results in other facts or issues being reviewed deferentially based solely on the fact findings of the Board. Indeed, we do not decide whether a given dispute could be parsed into discrete "issues” or facts so that such a determination could be made, or if it could, how a court would draw the line between such facts or issues.
. The trial court’s failure to apply the de novo standard, if error, was harmless error, for surely the result would have been the same under non-deferential review.
. Wang correctly points out that the district court misstated our case law on the test for the "motivation to combine” issue when it stated that “there must have been some
explicit
teaching or suggestion in the art to motivate one of even ordinary skill to combine such elements so as to create the same invention.”
Winner,
. WuROC, which disclosed a chamber capable of accepting either a dead-bolt or a ratcheting mechanism, may have informed one of ordinary skill in the art that both mechanisms would work, but it did not specifically disclose any such mechanisms and did not suggest that one should be replaced with the other. Grimaldi disclosed a rod and pawl design that was an anti-theft device attached to the clutch rather than a steering wheel. The district court did not clearly err in finding that “WuROC and Grimaldi in and of themselves would certainly not provide much guidance as to how to construct the Wu '047 device” and that if Johnson was not combined "with some form of a ratchet mechanism, then the fact that Wu '047 may have borrowed some elements from WuROC and Gri-maldi becomes irrelevant.”
Winner,
. The fact that the motivating benefit comes at the expense of another benefit, however, should not nullify its use as a basis to modify the disclosure of one reference with the teachings of another. Instead, the benefits, both lost and gained, should be weighed against one another.
