Audible, Inc. (“Audible”) appeals the decision of the United States District Court for the Western District of Washington to deny Audible’s motion for attorney fees under 35 U.S.C. § 285 including its request for additional discovery to develop the § 285 claim. We heard oral argument on September 5, 2007. Because we discern no clear error in the district court’s finding that the case is not exceptional and because we conclude the court did not abuse its discretion in denying additional discovery, we affirm.
I
Digeo, Inc. (“Digeo”) purchased U.S. Patent No. 5,734,823 (“'823 patent”) “as is” from IPDN Corporation, the successor in interest to Microtome, Inc., at a bankruptcy estate sale on August 12, 2002. The '823 patent is entitled, “Systems and Apparatus for Electronic Communication and Storage of Information,” (e.g., video pocket readers) with Michael Saigh, Douglas Brockhouse, Edward Chang, and Hsiao-Shih Chang listed as the inventors. Hsiao-Shih Chang is Edward Chang’s brother and goes by the informal name Oliver Chang.
The facts of this case read like a novel in that they involve the resurrection of an inventor thought to be deceased. Shortly prior to the bankruptcy estate sale, Digeo obtained the file history for the '823 patent, which contains riveting facts. A Power of Attorney (“POA”) was filed with the United States Patent and Trademark Office (“USPTO”) on July 25, 1996, 1 allegedly signed by Oliver Chang as the executor of the estate of his deceased brother, Edward Chang. Also filed on the same day was a separate POA by Oliver Chang, Saigh, and Brockhouse. The file history contains no document demonstrating that Edward Chang was deceased.
Both the issue fee transmittal dated July 22, 1997, and the '823 patent, which issued on March 31, 1998, list Microtome as the assignee, although the bankruptcy trustee did not file the assignments to Microtome with the USPTO until July 11, 2002, i.e., well after the patent had issued. In particular, there are July 1996 assignments to Microtome by (1) Oliver Chang, Saigh, and Brockhouse, and (2) Oliver Chang on behalf of Edward Chang. All assignments were notarized in July 1996, 2 predating the issuance of the '823 patent, but were not filed with the USPTO until a few weeks before the bankruptcy estate sale.
Digeo sued Audible for infringement of the '823 patent on March 23, 2005, almost two and a half years after Digeo had purchased the patent. 3 In its complaint, Digeo alleges that it is “the owner of all right, title, and interest in the '823 patent, including the right to sue for infringement *1366 of that patent.” Compl. ¶ 9. About a year into the litigation, Audible deposed the Changs on May 19, 2006 and discovered that Edward Chang was alive and residing in Los Angeles, CA and that Oliver Chang did not sign the documents purported to be the POAs and assignments. Audible also secured a license from Edward Chang to the '823 patent retroactive to the date of issuance. As a result, Audible moved for summary judgment (“MSJ”) and alternatively for dismissal on May 25, 2006, on the grounds that Digeo lacked standing because it did not possess complete ownership of the '823 patent and that Audible had a license under the '823 patent. In the MSJ, Audible also moved for attorney fees under § 285.
On August 24, 2006, the district court granted partial summary judgment in favor of Audible on Digeo’s claim of patent infringement. The district court concluded that because the assignments were forgeries, 4 they did not convey legal title to Digeo. 5 The summary adjudication was partially in favor of Audible because there was a material factual dispute as to whether Digeo had equitable title to the patent based on Edward Chang’s fiduciary or express contractual duty to assign his interest to Microtome. The district court also denied Audible’s § 285 motion because there was no evidence that Digeo knew or should have known about the forged documents.
On October 18, 2006, Digeo filed a voluntary motion to dismiss the complaint with prejudice. One day later, the Changs filed a motion to intervene. Audible filed an opposition to the motion to dismiss in which it renewed its § 285 motion and asked for limited discovery to develop its § 285 claim. 6
On December 1, 2006, the district court granted the motion to dismiss the complaint with prejudice
7
and denied the motion to intervene. The district court also denied Audible’s renewed motion for attorney fees and request for extension of discovery.
Digeo, Inc. v. Audible, Inc.,
No. 05-464,
II
We apply Federal Circuit case-law to the § 285 analysis, as it is unique to patent law.
Pharmacia & Upjohn Co. v. Mylan Pharms., Inc.,
If there is clear and convincing evidence that a plaintiff has brought a baseless or frivolous suit against an accused infringer, that is a sufficient basis to require a district court to deem the case exceptional under § 285.
See Forest Labs., Inc. v. Abbott Labs.,
Ill
On appeal, Audible argues that the district court committed error by switching the burden of proof to Audible to show that Digeo had not performed an appropriate pre-suit investigation, rather than leaving that burden with Digeo, in contravention of
View Engineering, Inc. v. Robotic Vision Systems, Inc.,
View Engineering,
where we, applying Ninth Circuit caselaw, affirmed a district court’s award of sanctions against a law firm for failure to make a reasonable inquiry into the facts prior to filing in
*1368
fringement counterclaims, is a case interpreting Rule 11 of the Federal Rules of Civil Procedure, not 35 U.S.C. § 285.
Once a litigant moves based upon non-frivolous allegations for a Rule 11 sanction, the burden of proof
shifts
to the non-movant to show it made a reasonable pre-suit inquiry into its claim.
View Eng’g,
Therefore, the burden here is not on Digeo to show it conducted a reasonable pre-suit investigation into its infringement
*1369
claim, namely an investigation of its legal title to the '823 patent, as in a Rule 11 context. Instead, the burden is on Audible to prove by clear and convincing evidence that the case is exceptional by showing that Digeo brought a frivolous lawsuit because it knew or should have known that it lacked legal title to the '823 patent.
See Haynes Int’l Inc. v. Jessop Steel Co.,
IV
Audible advocates on appeal, albeit without legal support, for a heightened standard of pre-suit investigation when a patent holder purchases a patent “as is.” See Appellant’s Br. at 17 (“[WJhere a plaintiff has bought rights ‘AS IS’ and without any representations or warranties, the mandatory pre-suit investigation must consist of something more than reading the file history.”). Per Audible, Digeo ignored red flags, such as the absence of an assignment to Microtome in the file history of the '823 patent; a change in Hsiao Chang’s signature; no proof of Edward Chang’s death; and an “as is” sale. Audible also cites as a further indicium of an inadequate pre-suit investigation, the lack of evidence that Digeo read the file history of the '823 patent. We disagree with Audible’s expansive reading of § 285, for we have never required a heightened investigation into the legal title of all patents purchased “as is.” We decline to do so now.
Rather, we have stated that merely negligent conduct does not suffice to establish that a case is exceptional.
See Mach. Corp. of Am. v. Gullfiber AB,
The pertinent inquiry here is whether Digeo knew or should have known its legal title was defective,
Haynes,
V
We review the district court’s denial of additional discovery, an issue not unique to patent law, for abuse of discretion, applying the law of the regional circuit.
Qualls v. Blue Cross, Inc.,
In denying Audible’s request for additional discovery, the district court found that Audible’s motion was based on its unsubstantiated speculation that Digeo had engaged in culpable pre-suit conduct.
See
Dismissal Order,
The district court balanced Audible’s assertion that additional discovery would produce evidence of Digeo’s culpable conduct against the expenditure of resources discovery would require and determined that additional discovery was not warranted. In so doing, the district court found that Audible’s request for additional discovery was based on “unsubstantiated speculation” of Digeo’s misconduct.
Id.
Audible’s “unsubstantiated speculation” about Digeo’s conduct does not demonstrate a “reasonable probability that the outcome [of its § 285 motion] would have been different had discovery been allowed.”
Laub,
Additionally, Audible discovered that Edward Chang was alive no later than May 19, 2006, when it deposed him. Yet, even armed with this information, Audible did not seek to depose anyone regarding Digeo’s pre-suit conduct until at least October 6, 2006, when it filed a case disposition brief containing a request for additional discovery.
This is a unique case involving an unusual set of facts — a not-so-dead inventor, forged documents, no evidence of culpabili *1371 ty, and a late discovery request. Audible sought additional discovery based on nothing more than a hunch that Digeo conducted an inadequate pre-suit investigation, and Audible did not seek additional discovery diligently. The district court’s denial of additional discovery under these circumstances certainly does not rise to the level of abuse required before we can overturn its decision.
VI
Because we find no clear error in the district court’s finding that this case is not exceptional and because we see no abuse of discretion in its denial of additional discovery, the decision of the district court is
AFFIRMED.
Notes
.July 25, 1996 is also the filing date of U.S. Application No. 08/687,292, which issued as the '823 patent.
. Because the assignments allegedly predate the filing date of the application, we wonder why the purported POAs are signed by the inventors and not by Microtome.
. Digeo also sued other parties for patent infringement prior to the instant suit, but those cases settled.
. Although the district court used the term “forgery” to denote that there was no evidence that Oliver Chang signed the documents or authorized their creation, the court explained that it was not opining on whether anyone had committed the criminal offense of forgery.
. The trial court based this ruling in part on the undisputed testimony by Hsiao-Shih Chang that he did not sign tire purported assignments and POAs and by the notary public who believed she did not notarize the assignments in question.
. In its opposition brief, Audible cited its Case Disposition Brief of October 6, 2006, in which it had previously moved for additional discovery.
. The trial court also dismissed without prejudice Audible’s counterclaims for a declaration of invalidity and unenforceability of the '823 patent.
. The trial court clarified this order on December 20, 2006.
. One key difference is that Rule 11 motions must comply with the safe harbor provision, but § 285 motions need not. See generally Fed.R.Civ.P. 11.
. We observe that the "Ninth Circuit defines a frivolous claim or pleading for Rule 11 purposes as one that is 'legally or factually "baseless” from an objective perspective ... [and made without] a reasonable and competent inquiry.’ ”
Q-Pharma,
.Digeo contends that it should receive fees for having to defend Audible’s objectively baseless Rule 11 argument. We disagree. Although Audible’s attempt to graft Rule 11 precedent onto § 285 caselaw is unpersuasive, it certainly is not sanctionable.
. Although most of these § 285 cases address situations where there is no reasonable ground for infringement, we extend them to situations such as the present one where there could not possibly be a reasonable ground for patent infringement if there is no legal title to the patent.
. The USPTO must have received instructions that Microtome was the assignee from *1370 somewhere, although the purported assignments were not filed until July 11, 2002.
