Pictiva Displays International Ltd. v. Samsung Electronics Co., Ltd. et al, No. 2:23-cv-00495 (E.D. Tex. Oct. 19, 2025)

Before the Court is the Motion to Strike Defendants’ Amended Answer, filed by Plaintiffs Pictiva Displays International Ltd. and Key Patent Innovations Limited. Dkt. No. 393. For the reasons discussed below, the Motion is GRANTED as to Defendants’ shop rights/employed-to-invent defenses and otherwise DENIED.

I. BACKGROUND

On April 21, 2024, the Court issued the Docket Control Order in this case, which set November 19, 2024, as the deadline to file amended pleadings. Dkt. No. 40 at 5. On November 19, 2024, Defendants filed their Answer to Plaintiffs’ First Amended Complaint. Dkt. No. 114. However, on December 17, 2024, Plaintiffs filed their Second Amended Complaint (“SAC”), adding Key Patent Innovations Limited as a Plaintiff (Dkt. No. 124), which was in response to the Court’s Order (Dkt. No. 118) resolving Defendants’ motion to dismiss the First Amended Complaint for lack of standing (Dkt. No. 57).¹

2On January 2, 2025, Defendants moved to dismiss the SAC under FRCP Rule 12(b)(6). Dkt. No. 141. On May 29, 2025, the Court granted in part Defendants’ 12(b)(6) Motion. Dkt. No. 295 (Dismissing member case 2:24-cv-00532 due to claim splitting and otherwise denying the motion). On June 12, 2025, Defendants filed their Answer to Plaintiffs’ SAC (“June 12 Answer”). Dkt. No. 361. By this time, fact discovery had already closed. Dkt. No. 40 at 3 (Docket Control Order setting fact discovery cutoff to March 17, 2025).

II. APPLICABLE LAW

In evaluating whether to strike an untimely amendment to an answer, this Court’s well-known four-factor test is employed. See Plastronics Socket Partners, Ltd. v. Dong Weon Hwang, No. 2:18-CV-00014-JRG-RSP, 2019 WL 5700797 (E.D. Tex. Apr. 17, 2019). Those four factors are: (1) the explanation for the failure to timely comply with the scheduling order; (2) the importance of the modification; (3) the potential prejudice in allowing the modification; and (4) the availability of a continuance to cure such prejudice. See id.

III. ANALYSIS

A. Timeliness

In the Motion, Plaintiffs argue that Defendants’ June 12 Answer was filed months after the amended pleadings deadline set out in the Docket Control Order and is, therefore, untimely. See Dkt. No. 393. As a result of this, Plaintiffs assert that the newly raised affirmative defenses and theories appearing for the first time in the June 12 Answer should be stricken. Id. at 4. In support of this, Plaintiffs point out that (1) their First Amended Complaint and SAC are substantively identical (the only change being that the SAC added Key Patent Innovations Limited as a plaintiff); and (2) that because of this, Defendants needed to seek leave of the Court before they could add their new arguments found in the June 12 Answer. Id. at 4–5 (citing e.g. Tech Pharmacy3 Servs., LLC v. Alixa Rx LLC, No. 4:15-cv-766, 2017 WL 2911773, at *2 (E.D. Tex. Jan. 19, 2017)).

In response, Defendants argue that their June 12 Answer is timely since it was filed within fourteen days after the Court’s Order resolving Defendants’ 12(b)(6) motion, and that they had, as a matter of right, the ability to file within this period. Dkt. No. 407 at 1 (citing FED. R. CIV. P. 12(a)(4)). They further argue that, regardless of Rule 12(a)(4), all of their allegedly new defenses were previously disclosed, and there is no prejudice to Plaintiffs. Id. at 1–2.

The Court finds that portions of Defendants’ June 12 Answer are untimely and that Defendants misapprehend the effect of Rule 12(a)(4). While ordinarily Rule12(a)(4) allows a party to file an answer to a complaint within fourteen days of a Rule 12(b) motion being denied, and without first having to receive leave from the court, see, e.g., Beardmore v. Jacobson, No. 4:13-CV-361, 2014 WL 3543726, at *7 (S.D. Tex. Jul. 14, 2014), this Court has made clear that this only applies where “the amended complaint changes the theory or scope of the case,” Tech Pharmacy Servs., LLC v. Alixa Rx LLC, No. 4:15-CV-766, 2017 WL 2911773, at *1–2 (E.D. Tex. Jan. 19, 2017).

Here, as Plaintiffs suggest, there are no substantive differences between their Complaints. See Dkt. No. 17; compare Dkt. No. 124; see also Dkt. No. 393-1 (redline comparison of FAC and SAC). In the absence of such differences, Defendants were required to first receive leave from the Court to file an answer that raises new theories.² The reason is that, “[i]f every amendment, no matter how minor or substantive, allowed defendants to assert counterclaims or defenses as of right, claims that would otherwise be barred or precluded could be revived without cause,” and “[t]his would deprive the Court of its ability to effectively manage the litigation.” Tinnus Enters., LLC v. Telebrands Corp., No. 6:16-CV-0033, 2017 WL 11630433, at *2 (E.D. Tex. July 11, 2017)4 (quoting E.E.O.C. v. Morgan Stanley & Co., Inc., 211 F.R.D. 225, 227 (S.D.N.Y. 2002)). The Court finds that, because Defendants did not seek leave to file their June 12 Answer, and it was filed after the amended pleadings deadline, the new portion of the Answer is untimely.

B. Prejudice

In line with the prior analysis, there may be certain circumstances under which an untimely answer is still permissible. See supra Section II. However, Plaintiffs argue that Defendants are without excuse for adding new defenses so late in the litigation, asserting that there has not been any late-breaking evidence on which Defendants base their amendments. See Dkt. No. 393 at 6. They further argue that because of the stage, they would be significantly prejudiced due to the close of fact discovery and a lack of opportunity to investigate the new defenses. See id. at 5.

In response, Defendants argue that there is no prejudice because the new defenses were already pleaded in their Answer to Plaintiffs’ First Amended Complaint. Dkt. No. 407 at 1–2 (citing Dkt. No. 114). They further argue that Plaintiffs cannot validly claim surprise about these defenses since they were previously the subject of motions for summary judgment filed by Plaintiffs and discussed in Plaintiffs’ experts’ reports. See id. at 2, 10.

There are five defenses at issue in the June 12 Answer: Defendants’ defense of (1) improper inventorship; (2) an allegedly new prosecution history estoppel defense related to Plaintiffs’ assertion of the doctrine of equivalents; (3) a shop rights/employed-to-invent defense; an inequitable conduct defense; and (5) a marking defense on damages.

With respect to the improper inventorship defense, Defendants point to a side-by-side comparison of their answer to the First Amended Complaint and the SAC in support of their argument that they had already pleaded this defense:

5Dkt. No. 407 at 3. They further point to their April 2024 Initial Disclosures, June 2024 Corrected Invalidity Contentions, and the March 2025 Opening Report of Samsung’s Expert Dr. Katona in support of their argument that, to the extent that they had not already pleaded this defense, Plaintiffs were nonetheless on sufficient notice and are therefore not prejudiced:

6Id. at 6–7.

Having reviewed Defendants’ April 2024 Initial Disclosures and June 2024 Corrected Invalidity Contentions,³ the Court is satisfied that Plaintiffs were sufficiently apprised of this defense. Both aforementioned documents were served on Plaintiffs well in advance of the discovery cut-off (See Dkt. No. 40 at 3), and they contained enough details for Plaintiffs to pursue relevant discovery. We note with particularity, however, that Defendants will be held to what they disclosed to Plaintiffs during discovery.⁴

With respect to the prosecution history estoppel defense, Defendants’ again point to a side-by-side comparison of their answer to the First Amended Complaint and the SAC in support of their argument that they had already pleaded this defense:

7Dkt. No. 407 at 3–4. They further point to their January 2025 Responsive Claim Construction Brief and their June 2024 Supplemental Response to Plaintiffs’ Interrogatories Set One in support of their argument that, to the extent that they had not already pleaded this defense, Plaintiffs were nonetheless on sufficient notice and are therefore not prejudiced:

8Id. at 7.

The Court is satisfied that Plaintiffs were sufficiently apprised of Defendants’ prosecution history estoppel defense. Enough details were contained within Defendants’ answer to the First Amended Complaint such that Plaintiffs could pursue relevant discovery. Plaintiffs’ only argument specific to this defense is that Defendants failed to identify any statement in any asserted patent’s prosecution history giving rise to estoppel. Dkt. No. 393 at 7. While again holding Defendants to what they disclosed during discovery, the Court finds Plaintiffs’ arguments unpersuasive. There was sufficient specificity of the theory to allow Plaintiffs to investigate the matter.

With respect to the shop rights/employed-to-invent defense, Defendants’ side-by-side comparison is as follows:

9Dkt. No. 407 at 4. They further point to the March 2025 Opening Report of Dr. Katona and their May 2025 Opposition to Plaintiffs’ Motion for Summary Judgment on Certain Affirmative Defenses in support of their argument that, to the extent that they had not already pleaded this defense, Plaintiffs were on sufficient notice and are therefore not prejudiced:

Id. at 7.

10The Court finds Defendants’ arguments unpersuasive. First, the totality of what is said in Defendants’ Answer to the First Amended Complaint is little more than a boilerplate generic catch-all, which is insufficient to inform Plaintiffs of what specific issue (namely, a shop rights defense) they need to seek discovery on. Second, the March 2025 Opening Report of Dr. Katona and Defendants’ May 2025 Opposition to Plaintiffs’ Motion for Summary Judgment on Certain Affirmative Defenses both came after the close of fact discovery; thus, this does little to ameliorate the prejudice to Plaintiffs.

Accordingly, the Motion to Strike on this basis is GRANTED and Defendants’ shop rights/ employed-to-invent defenses are hereby STRICKEN.

With respect to the inequitable conduct defense, Defendants’ side-by-side comparison is as follows:

Dkt. No. 407 at 4. They further point to, inter alia, their June 2024 Corrected Invalidity Contentions in support of their argument that, to the extent that they had not already pleaded this defense, Plaintiffs were on sufficient notice and are therefore not prejudiced:

11Id. at 7–8.

The Court is satisfied that Plaintiffs were sufficiently apprised of Defendants’ inequitable conduct defense. Defendants’ June 2024 Corrected Invalidity Contentions provide sufficient detail for Plaintiffs to be able to properly investigate this defense. See Dkt. No. 407-3 at 277–81.

Finally, with respect to the marking defense on damages, Defendants point one last time to a side-by-side comparison of their answer to the First Amended Complaint and the SAC:

12Dkt. No. 407 at 4–5. They further point to their February 2025 Arctic Cat letter in support of their argument that, to the extent that they had not already pleaded this defense, Plaintiffs were on sufficient notice and are therefore not prejudiced:

Id. at 7–8.

The Court is satisfied that Plaintiffs were sufficiently apprised of Defendants’ marking defense. Defendants sent Plaintiffs an Arctic Cat letter with almost a full month left in discovery.13 .

See Dkt. No. 407-9 at 3 (Letter dated February 21, 2025); compare Dkt. No. 40 at 3. This is sufficient under the facts of this case.

IV. CONCLUSION

For the reasons discussed above, the Motion is GRANTED as to Defendants’ shop rights/employed-to-invent defenses and otherwise DENIED.

SIGNED this 3rd day of January, 2012.

SIGNED this 19th day of October, 2025.

ROY S. PAYNE

UNITED STATES MAGISTRATE JUDGE