Lack of Diligence in Deposing Key Inventor Precludes Amending Answer to Add Inequitable Conduct Defense

January 17, 2024

Reading Time : 2 min

The Central District of California denied a defendant’s motion for leave to amend to allege inequitable conduct due to the defendant’s delay in deposing a key inventor until the end of fact discovery. The district court held that the defendant neither exercised diligence nor established good cause based on the inventor’s deposition to warrant amending its answer.

In a patent infringement lawsuit over printer and printing method patents, Defendant deposed the first named inventor of the patents two weeks before the end of fact discovery. The inventor testified that he had used information about a printhead manufactured by a third party in the design of the claimed inventions. Patentee then produced related documents after the deposition and two days before the close of fact discovery. Defendant argued that Patentee intentionally withheld this critical information about the printhead until the end of discovery, depriving Defendant of the ability to allege inequitable conduct sooner. Defendant filed a motion to amend its answer to assert inequitable conduct following the Patentee’s production—eight months after the deadline to amend pleadings.

Patentee argued in opposition to the motion that it had produced relevant documents about the claimed invention’s functionality earlier in the case, that the information that formed the basis for Defendant’s motion was cumulative of prior discovery and that the information was not material to patentability. Patentee further argued that Defendant was at fault for delaying the deposition at which it learned of the printhead information until two weeks before the end of fact discovery and four months before trial. Thus, Defendant was not diligent.

The court agreed with Patentee, concluding that Defendant was not diligent and thus failed to show good cause to modify the court’s scheduling order pursuant to Rule 16(b)(4) long after the deadline to amend pleadings. Although Defendant noticed the deposition in March and the parties had a dispute over its location, the district court faulted Defendant for waiting several months to bring the location dispute to its attention. The court also found that Defendant failed to identify any testimony that supported a “sudden revelation of inequitable conduct.” The court also held that Defendant failed to meet the requirements to amend its pleading under Rule 15 because, inter alia, it failed to alleged facts sufficient to support a reasonable inference of specific intent.

Practice Tip: When choosing the timing of key depositions, parties must consider the potential consequences of discovering relevant information late in the discovery period. Courts may be reluctant to permit amendments or additional discovery when it is likely to be time-consuming, costly or delay resolution of the case even if that discovery was requested, but not provided earlier in the case if the requesting party did not seek the court’s assistance in ensuring that such discovery was provided earlier.

MGI Digital Technology SA v. Duplo USA Corporation, 8-22-cv-00979 (CDCA Oct. 17, 2023).

Share This Insight

Previous Entries

IP Newsflash

January 24, 2025

The District of Delaware recently rejected a patentee’s argument that non-production of an opinion letter from counsel, combined with knowledge of the patent, warranted a finding that defendant induced infringement.

...

Read More

IP Newsflash

January 17, 2025

The District of Delaware recently denied a motion to dismiss a patent infringement complaint involving gene editing technology that sought relief under the Safe Harbor Provision of the Hatch-Waxman Act. Specifically, the court found the patentee’s complaint sufficiently alleged at least some uses of the claimed technology that, when taken as true, were not solely uses of a “patented invention” that were “reasonably related” to an FDA submission.

...

Read More

IP Newsflash

January 17, 2025

The District of Arizona recently held that a plaintiff’s failure to mark patented products during the time period that marking was required barred it from recovering all pre-notice damages, including for a period of time when there was no obligation to mark.

...

Read More

IP Newsflash

January 16, 2025

The Unified Patent Court (UPC) aims to provide expeditious decisions for its litigants. That means that there is a higher bar for obtaining extensions of time. As exemplified in BMW v. ITCiCo, the UPC’s reluctance to grant extensions can have serious consequences, including revocation of the patent.

...

Read More

IP Newsflash

January 15, 2025

The Patent Trial and Appeal Board granted institution of inter partes review of a patent directed to delivery of targeted television advertisements. The board rejected patent owner’s argument that a lack of particularity as to the asserted grounds justified denial under 35 U.S.C. § 312(a), holding that “simply including a significant amount of testimony and a number of supporting references is not, by itself, a reason to find that the particularity requirement is not met.”

...

Read More

IP Newsflash

December 2, 2024

The Patent Trial and Appeal Board determined that a reference could be used as prior art because patent owner failed to provide sufficient evidence that the prior art’s disclosure was invented by all four named inventors, and thus the same “inventive entity,” as the challenged claims.

...

Read More

IP Newsflash

December 2, 2024

The Patent Trial and Appeal Board rejected a patent owner’s assertion that petitioner should have named a third party, which was a defendant in a related district court patent infringement litigation and a party to a joint defense agreement (JDA) with petitioner, as a real party-in-interest (RPI). Had the board ruled otherwise and found the third party to be an RPI, the petition would have been time-barred under 35 U.S.C. § 315(b).

...

Read More

IP Newsflash

November 27, 2024

A district court recently refused to exclude testimony regarding consumer surveys conducted by a design patent expert, holding instead that the consumer surveys may be probative of how an ordinary observer would view the designs at issue, and thus could assist the factfinder in determining design patent infringement under the ordinary observer test.

...

Read More

© 2025 Akin Gump Strauss Hauer & Feld LLP. All rights reserved. Attorney advertising. This document is distributed for informational use only; it does not constitute legal advice and should not be used as such. Prior results do not guarantee a similar outcome. Akin is the practicing name of Akin Gump LLP, a New York limited liability partnership authorized and regulated by the Solicitors Regulation Authority under number 267321. A list of the partners is available for inspection at Eighth Floor, Ten Bishops Square, London E1 6EG. For more information about Akin Gump LLP, Akin Gump Strauss Hauer & Feld LLP and other associated entities under which the Akin Gump network operates worldwide, please see our Legal Notices page.