Seagen Inc.

Patent Trials and Appeals Board

Jun 24, 2021

PGR2021-00030 (P.T.A.B. Jun. 24, 2021)

Trials@uspto.gov Paper 11
571-272-7822 Entered: June 24, 2021

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

DAIICHI SANKYO, INC. AND
ASTRAZENECA PHARMACEUTICALS, LP,
Petitioner,

v.

SEAGEN INC.,
Patent Owner.

Case PGR2021-00030
Patent 10,808,039 B2

Before ERICA A. FRANKLIN, SHERIDAN K. SNEDDEN, and
CHRISTOPHER M. KAISER, Administrative Patent Judges.

SNEDDEN, Administrative Patent Judge.

DECISION
Denying Institution of Post-Grant Review
35 U.S.C. § 324

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I. INTRODUCTION
Daiichi Sankyo, Inc. and AstraZeneca Pharmaceuticals, LP
(collectively “Petitioner”) filed a Petition requesting a post-grant review of
claims 1–5, 9, and 10 of U.S. Patent No. 10,808,039 (“the ’039 patent,” Ex.
1001). Paper 1 (“Pet.”). Seagen Inc. (“Patent Owner”) filed a Preliminary
Response to the Petition. Paper 7 (“Prelim. Resp.”). Petitioner filed a Reply
to Patent Owner’s Preliminary Response. Paper 8 (“Reply”). Patent Owner
filed a sur-reply to Petitioner’s Reply. Paper 9 (“Sur-reply”).
We have authority to determine whether to institute a post-grant review.
35 U.S.C. § 324(c); 37 C.F.R. § 42.4(a). The standard is set forth in
§ 324(a), which provides that a post-grant review shall not be instituted
unless “the Director determines that the information presented in the petition
filed under section 321, if such information is not rebutted, would
demonstrate that it is more likely than not that at least 1 of the claims
challenged in the petition is unpatentable.”
After considering the Petition and the Preliminary Response, and the
evidence cited therein, we exercise our discretion under 35 U.S.C. § 324(a)
to deny institution.
A. Real Parties in Interest and Related Proceedings
Petitioner identifies Daiichi Sankyo Company, Limited and
AstraZeneca UK Limited and Petitioners Daiichi Sankyo, Inc. and
AstraZeneca Pharmaceuticals, LP as real parties in interest. Pet. 88.
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Patent Owner identifies Seagen Inc. as a real party in interest.
Paper 5, 1.
B. Related Matters
Petitioner filed a separate Petition for post-grant review of Claims 6–8
of the ’039 patent as IPR2021-00042.
The parties list the following co-pending matters:
Daiichi Sankyo Co., Ltd. v. Seattle Genetics, Inc., No. 1:19-cv-02087-
LPS (D. Del.) (closed Nov. 13, 2020);
Seattle Genetics, Inc. v. Daiichi Sankyo Co., Ltd., American
Arbitration Association Case No. 01-19-0004-0115 (Brown, Arb.);
Seagen Inc. v. Daiichi Sankyo Co., Ltd., No. 2:20-cv-00337 (E.D.
Tex.) (“the Texas Litigation”);
Daiichi Sankyo, Inc. et al. v. Seattle Genetics, Inc., No. 1:20-cv-
01524-LPS (D. Del.) (“the Delaware Litigation”). Pet. 83; Paper 5, 1.
Patent Owner identifies the following US patents and pending
published applications that claim the benefit of priority of the filing date of
the ’039 patent: US 7,498,298; US 7,994,135; US 7,964,566; US 7,964,567;
US 7,745,394; US 8,703,714; US 8,557,780; US 10,414,826; US
10,808,039; US 2020/0347149. Paper 5, 1–2.
C. The ’039 Patent
The ’039 patent discloses antibody-drug conjugates (“ADCs”).
Ex. 1001, 1:58–63. “The drug moiety (D) of the [ADCs] are of the
dolastatin/auristatin type[,] which have been shown to interfere with
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microtubule dynamics, GTP hydrolysis, and nuclear and cellular division.”
Id. at 71:21–25 (citations omitted).
Embodiments of this invention can take many forms, including having
the formula:

Id at 70:18–30.
The formula’s components can change, such as one embodiment
where “an antibody drug conjugate (ADC), or a pharmaceutically acceptable
salt or solvate thereof, wherein Ab is an antibody that binds one of the
tumor-associated antigens.” Id. at 111:33–37. Digestion of antibodies can
produce two identical antigen-binding fragments, called “Fab” fragments.
Id. at 27:14–15. Fab fragments can differ, such as some including a few
cysteine residues at the carboxy terminus of the heavy chain CH3 domain
and at least one free thiol group. Id. at 27:36–43.
In some units, there is a Stretcher unit that, when present, is capable of
linking a Ligand unit to an amino acid unit. For example, in one
embodiment, “the Stretcher unit forms a bond with a sulfur atom of the
Ligand unit. The sulfur atom can be derived from a sulfhydryl group of a
Ligand.” Id. at 63:54–56.
The peptide unit on the ADC can vary in size. The peptide unit can be
a “dipeptide, tripeptide, tetrapeptide, pentapeptide, hexapeptide,
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heptapeptide, octapeptide, nonapeptide, decapeptide, undecapeptide or
dodecapeptide unit.” Id. at 65:49–53.
The R19 groups on the peptide chain can be selected from, but is not
limited to, the groups of “hydrogen, methyl, isopropyl, isobutyl, sec-butyl,
benzyl, p-hydroxybenzyl, —CH2OH, —CH(OH)CH3, —CH2CH2SCH3, —
CH2CONH2, —CH2COOH, —CH2CH2CONH2, —CH2CH2COOH, —
(CH2)3NHC(═NH)NH2, —(CH2)3NH2, —(CH2)3NHCOCH3, —
(CH2)3NHCHO, —(CH2)4NHC(═NH)NH2, —(CH2)4NH2, —
(CH2)4NHCOCH3, —(CH2)4NHCHO, —(CH2)3NHCONH2, —
(CH2)4NHCONH2, —CH2CH2CH(OH)CH2NH2, 2-pyridylmethyl-, 3-
pyridylmethyl-, 4-pyridylmethyl-, phenyl, cyclohexyl,
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Id. at 65:65–66:43.
The spacer unit, Y, “when present, links an Amino Acid unit to the
Drug moiety when an Amino Acid unit is present.” Id. at 68:14–16. In some
embodiments, “y is 0, 1, or 2.” Id. at 6:47. The average number of drugs
per antibody in a molecule of a particular formula, p, can range from 1 to 20
(D) drugs per antibody. Id. at 61:44–46.
In some embodiments of the invention, “a substantial amount of the
drug moiety is not cleaved from the antibody until the antibody-drug
conjugate compound enters a cell with a cell-surface receptor specific for the
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antibody of the antibody-drug conjugate, and the drug moiety is cleaved
from the antibody when the antibody-drug conjugate does enter the cell.”
Id. at 18:56–61. In other aspects of the invention, “the bioavailability of the
[ADC] or an intracellular metabolite . . . is improved when compared to a
drug compound comprising the drug moiety of the [ADC], or when
compared to an analog of the compound not having the drug moiety.” Id. at
18:62–67.
D. Illustrative Claim
Claim 1, the only independent claim, is illustrative and reproduced
below.
1. An antibody-drug conjugate having the formula:

or a pharmaceutically acceptable salt thereof, wherein:
Ab is an antibody,
S is sulfur,
each —Ww— unit is a tetrapeptide; wherein each —W—
unit is independently an Amino Acid unit having the formula
denoted below in the square bracket:

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wherein R19 is hydrogen or benzyl,
Y is a Spacer unit,
y is 0, 1 or 2,
D is a drug moiety, and
p ranges from 1 to about 20,
wherein the S is a sulfur atom on a cysteine residue of the
antibody, and
wherein the drug moiety is intracellularly cleaved in a
patient from the antibody of the antibody-drug conjugate or an
intracellular metabolite of the antibody-drug conjugate.
Ex. 1001, 331:36–332:40.

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E. The Asserted Grounds of Unpatentability
Petitioner asserts the challenged claims are unpatentable on the
following grounds:
Basis/Reference Statutory
Basis
Challenged
Claims
Written Description § 112(a) 1–5, 9, 10
Enablement § 112(a) 1–5, 9, 10
Failing to particularly point out and
distinctly claim that which the inventor or a
joint inventor regards as his or her
invention
§ 112(b) 1–5, 9, 10
Ogitani1 § 102 1–5, 9, 10
Pet. 5.
Petitioner relies on the Declaration of Dr. John M. Lambert, Ph.D.
(Ex. 1002) in support of the Petition.
II. ANALYSIS
A. Discretion under 35 U.S.C. § 324
35 U.S.C. § 324(a) states that
[t]he Director may not authorize a post-grant review to be
instituted unless the Director determines that the information
presented in the petition filed under section 321, if such
information is not rebutted, would demonstrate that it is more

1 Ex. 1009, Ogitani, Yusuke et al., Bystander Killing Effect of DS-8201a, a
Novel Anti-Human Epidermal Growth Factor Receptor 2 Antibody-Drug
Conjugate, in Tumors with Human Epidermal Growth Factor Receptor 2
Heterogeneity, 107 CANCER SCI. 1039 (June 22, 2016) (“Ogitani”).

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likely than not that at least 1 of the claims challenged in the
petition is unpatentable.
The portion of the statute reading “[t]he Director may not authorize . . .
unless” mirrors the language of 35 U.S.C. § 314(a), which concerns inter
partes review. This language of sections 314(a) and 324(a) provides the
Director with discretion to deny institution of a petition. See Cuozzo Speed
Techs., LLC v. Lee, 136 S. Ct. 2131, 2140 (2016) (“[T]he agency’s decision
to deny a petition is a matter committed to the Patent Office’s discretion.”);
Consolidated Trial Practice Guide November 2019 (“TPG”)2 at 55.
In exercising the Director’s discretion under 35 U.S.C. §§ 314(a) and
324(a), the Board may consider “events in other proceedings related to the
same patent, either at the Office, in district courts, or the ITC.” TPG at 58.
The Board’s precedential NHK Spring decision explains that the Board may
consider the advanced state of a related district court proceeding, among
other considerations, as a “factor that weighs in favor of denying the Petition
under § 314(a).” NHK Spring Co. v. Intri-Plex Techs., Inc., IPR2018-00752,
Paper 8 at 20 (PTAB Sept. 12, 2018) (precedential).
Additionally, the Board’s precedential Fintiv Order identifies several
factors to be considered when analyzing issues related to the Director’s
discretion to deny institution, with the goal of balancing efficiency, fairness,
and patent quality. See Apple Inc. v. Fintiv, Inc., IPR2020-00019, Paper 11
at 5‒6 (PTAB Mar. 20, 2020) (precedential) (“the Fintiv Order”). These
factors include: 1) whether a stay exists or is likely to be granted if a

2 Available at https://www.uspto.gov/TrialPracticeGuideConsolidated.
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proceeding is instituted; 2) proximity of the court’s trial date to the Board’s
projected statutory deadline; 3) investment in the parallel proceeding by the
court and parties; 4) overlap between issues raised in the petition and in the
parallel proceeding; 5) whether the petitioner and the defendant in the
parallel proceeding are the same party; and 6) other circumstances and
considerations that impact the Board’s exercise of discretion, including the
merits. Id.
We recognize that NHK Spring and the Fintiv Order apply the
Director’s discretion pursuant to 35 U.S.C. § 314(a), and do not specifically
extend their application to 35 U.S.C. § 324(a), which is the relevant statute
that applies to this PGR proceeding. As noted above, however, the pertinent
statutory language is the same in both section 314(a) and section 324(a).
Moreover, the overall policy justifications associated with the exercise of
discretion—inefficiency, duplication of effort, and the risk of inconsistent
results—apply to post-grant review proceedings under 35 U.S.C. § 324(a).
Accordingly, we apply the factors set forth in the Fintiv Order to the facts
here. See, e.g., Teva Pharms. USA, Inc. v. Corcept Therapeutics, Inc.,
PGR2019-00048, Paper 19 at 11 (PTAB Nov. 20, 2019) (analyzing NHK
Spring and instituting trial); Stripe, Inc. v. Boom! Payments, Inc.,
CBM2020-00002, Paper 22 (PTAB May 19, 2020) (analyzing the Fintiv
Order and instituting trial).
We, however, recognize that there are differences between inter
partes review and post-grant review that, when relevant to specific Fintiv
factors, may be considered. Those differences include the fact that the
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window for filing a petition for post-grant review is open only for nine
months from the date of issuance. See 35 U.S.C. § 321(c). Furthermore,
“[t]he intent of the post-grant review process is to enable early challenges to
patents, while still protecting the rights of inventors and patent owners
against new patent challenges unbounded in time and scope.” H.R. Rep.
No. 112-98, pt. 1, 47–48 (2011).
Patent Owner argues that we should exercise our discretion under
35 U.S.C. § 324(a) to deny institution due to the common issues being
litigated in parallel district court cases. Prelim. Resp. 18–32. We have
considered the circumstances and facts before us in view of the Fintiv
factors and determine that the circumstances presented here weigh in favor
of exercising discretion under § 324(a) to deny institution of post-grant
review.
1. Whether the court granted a stay or evidence exists that one
may be granted if a proceeding is instituted.
Patent Owner is concurrently engaged in two parallel district court
proceedings involving the ’039 patent with Daiichi Sankyo Co., Ltd. and
Daiichi Sankyo, Inc.—the Texas Litigation and the Delaware Litigation. See
Seagen Inc. v. Daiichi Sankyo Co., Ltd., No. 2:20-cv-00337 (E.D. Tex.); see
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Daiichi Sankyo, Inc. v. Seattle Genetics, Inc., No. 1:20-cv-01524-LPS (D.
Del.)3,4; Reply 1; Prelim. Resp. 20.
The Delaware Litigation has been stayed “pending a determination by
the Eastern District of Texas as to whether Seagen’s action in that court is
going to remain there.” Prelim. Resp. 5. The district court in the Texas
Litigation has not granted a stay, and Daiichi Sankyo Co., Ltd. has not
requested a stay. Reply 1. However, Petitioner claims Daiichi Sankyo Co.,
Ltd. will seek a stay upon institution. Id. Although the Delaware Litigation
has been stayed, it has been stayed pending the Texas Litigation, which may
resolve many of the issues of the Delaware Litigation. Accordingly, our
focus is on the Texas Litigation.
Petitioner argues that a post-institution stay in the Texas Litigation is
likely. Pet. 75–76. Petitioner states that the district court judge views
institution as “highly significant” and has granted a stay in fifteen of the
seventeen cases that the Board has instituted in parallel. Reply 1. Patent
Owner counters this by arguing that only 22 out of 30, or 73%, of post-
institution stay requests were granted and, of these 22 granted post-
institution stay requests, 16 were based off stipulated, unopposed, or patent
owner initiated motions. Sur-reply 1.

3 Seagen Inc. was formerly known as “Seattle Genetics, Inc.” Pet. 1.

4 Daiichi Sankyo, Inc. is a subsidiary of Daiichi Sankyo Co., Ltd., the
defendant in the Texas Litigation. Prelim. Resp. 27.
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We have considered the arguments and evidence presented by both
parties. We recognize that many legitimate reasons may lead a party not to
file a motion to stay a parallel proceeding prior to the Board’s institution
decision, including because such a motion may be viewed as premature. Be
that as it may, our precedential guidance instructs us to consider whether the
court has granted a stay of the parallel proceeding, or whether evidence
exists that a stay may be granted upon institution. Fintiv Order at 5–6. As it
stands, the record lacks sufficient evidence to suggest that a stay has been
granted, or may be granted in the future. It is a judge who determines
whether to grant a stay based on the facts of each specific case as presented
in the briefs by the parties. We decline to infer, based on actions taken in
different cases with different facts, how the district court judge would rule
should a stay be requested in the Texas Litigation.
For these reasons, we determine that the facts underlying this factor
are neutral.
2. Proximity of the court’s trial date to the Board’s projected
statutory deadline for a final written decision.
Trial for the parallel Texas Litigation is scheduled to begin on April 4,
2022. See Prelim. Resp. 22. Given the statutory deadlines, our latest
possible date for issuance of a final written decision in this proceeding is
July 26, 2022. 35 U.S.C. §§ 324(c), 326(a)(11) (2018); see 37 C.F.R.
§ 42.100(c). Thus, our projected statutory deadline for a final written
decision is about four months after the beginning of the Texas district
court’s trial.
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Petitioner argues that the trial date predates the final written decision
by a few months, and therefore, the decision whether to institute implicates
other factors, which favor institution. Reply 2.
“If the court’s trial date is earlier than the projected statutory deadline,
the Board generally has weighed this fact in favor of exercising authority to
deny institution under NHK.” Fintiv Order at 9. On the other hand, “[i]f the
court’s trial date is at or around the same time as the projected statutory
deadline or even significantly after the projected statutory deadline, the
decision whether to institute will likely implicate other factors discussed
herein, such as the resources that have been invested in the parallel
proceeding.” Id. For these reasons, where trial in the parallel proceeding is
scheduled to occur nearly four months prior to our Final Written Decision,
we determine that the facts underlying this factor weigh toward denying
institution.
3. Investment in the parallel proceeding by the court and the
parties.
Patent Owner argues that the parties have expended substantial
resources on discovery and exchanged infringement and invalidity
contentions in the Texas Litigation and that institution would only create
duplicative costs. Prelim. Resp. 24 (citing Ex. 2002, 2003). For example,
Patent Owner contends that the parties have exchanged a voluminous
amount of discovery documents, that Patent Owner will file its opening
claim construction brief on July 16, 2021, and that the parties have an
upcoming claim construction hearing scheduled for August 2021. Id. at 24;
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see also Fintiv Order at 9 (the Board considers “the amount and type of
work already completed in the parallel litigation by the court and the parties
at the time of the institution decision.”).
Petitioner argues that only investment completed at the time of the
institution decision is relevant to this factor. Reply 2. Petitioner contends
that there has not been significant resource investment by the court or parties
yet. Pet. 80. Petitioner also notes that it filed for post-grant review about
two months after patent issuance with the second petition filed about two
weeks after Patent Owner first alleged infringement of claims 6–8. Reply 3.
We have considered Patent Owner’s position but note that, at this
time, it appears considerable effort remains to be completed in the parallel
litigation. In particular, it does not appear that the district court has issued
any rulings as to claim construction and that important deadlines have not
yet occurred. On balance, the level of investment by the parties and the
court is not substantial.
Additionally, as part of our holistic analysis, we also consider the
speed in which Petitioner acted. See Apple Inc. v. Seven Networks, LLC,
IPR2020-00156, Paper 10 at 11–12 (PTAB June 15, 2020). Here, Petitioner
represents it acted diligently by filing the Petition two months after the
issuance of the ’039 Patent. Reply 3; Sur-reply 2. Because Petitioner acted
diligently and without much delay, this mitigates against the investment of
the parties. See Seven Networks, Paper 10 at 11–12. As Fintiv Order states,
“[i]f the evidence shows that the petitioner filed the petition expeditiously,
such as promptly after becoming aware of the claims being asserted, this fact
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has weighed against exercising the authority to deny institution under
NHK.” Fintiv Order at 11
Taken together, we find that this factor does not weigh for or against
the exercise of our discretion to deny institution pursuant to § 324(a).
4. Overlap between issues raised in the petition and in the parallel
proceeding.
Based on the facts provided in the record, we are unable to determine
if there is significant overlap in the issues addressed in the Texas Litigation
and Petitioner’s arguments. Petitioner does not argue lack of overlap
between the two respective tribunals either. See Reply 3 (“And the overlap
between the issues here and in court reinforces the likelihood of a stay . . .
.”). Indeed, Petitioner appears to concede that there are overlapping issues
in the Texas Litigation. Id. (“The litigation likely will be stayed before
overlapping issues are resolved.”). Patent Owner represents that the
“Petition relies on identical grounds for unpatentability as those at issue in
the [Texas Litigation].” Sur-reply 3; see also Ex. 2003 (the Texas Litigation
invalidity contentions).
Under the Fintiv Order, “if the petition includes the same or
substantially the same claims, grounds, arguments, and evidence as
presented in the parallel proceeding, this fact has favored denial” because
“concerns of inefficiency and the possibility of conflicting decisions [are]
particularly strong.” Fintiv Order at 12. Based on the record before us and
the representations made by Patent Owner, we determine that this factor on
balance weighs in favor of discretionary denial.
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5. Whether the petitioner and the defendant in the parallel
proceeding are the same party.
Petitioner argues that neither Daiichi Sankyo, Inc. nor AstraZeneca
Pharmaceuticals, LP are parties to the Texas Litigation. Pet. 80.
Additionally, Petitioner argues that Daiichi Sankyo, Inc. and AstraZeneca
Pharmaceuticals, LP could not have been named as Defendants in the Texas
Litigation. Id.
Patent Owner does not dispute that Petitioner is not a defendant in the
Texas Litigation. Prelim. Resp. 3. Rather, Patent Owner argues that the real
parties in interest in this proceeding and the Texas Litigation are the same.
Prelim. Resp. 27. Specifically, Patent Owner argues that “Daiichi Sankyo,
Inc. is the wholly-owned subsidiary of Daiichi Sankyo,” the Defendant in
the Texas Litigation. Id. (citing Ex. 2025); see also Pet. 82 (“Real parties-
in-interest include Petitioners Daiichi Sankyo, Inc. and AstraZeneca
Pharmaceuticals, LP, as well as Daiichi Sankyo Company, Limited and
AstraZeneca UK Limited.”). Patent Owner argues that “the parties to this
petition and the parties in the litigation share a clear corporate relationship,
and one that is specifically focused on the ’039 Patent and the accused
product” in the Texas Litigation. Prelim. Resp. 29. Patent Owner further
argues that Petitioner AstraZeneca “has already participated in discovery in
the Texas Action, and it is a party to the Delaware Action, where it opposed
a stay and requested that discovery also commence.” Id. at 30 (citing Ex.
2006).
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Under the Fintiv Order, “[i]f a petitioner is unrelated to a defendant in
an earlier court proceeding, the Board has weighed this fact against
exercising discretion to deny institution under NHK.” Fintiv Order at 13–14.
Given that the real parties in interest in this proceeding are parties to the
Texas Litigation, we determine that this factor on balance weighs in favor of
discretionary denial.
6. Other circumstances that impact the Board’s exercise of
discretion, including the merits.
When considering whether to exercise discretion to deny a petition,
we undertake a balanced assessment of all relevant circumstances in the
case, including the merits. Fintiv Order at 14. Although we need not
undertake a full merits analysis when evaluating Fintiv Factor 6, we consider
the strengths and weaknesses of the merits, where stronger merits may favor
institution and weaker merits may favor exercising discretion to deny
institution. Id. at 15–16. We also consider the other circumstances
identified by the parties as pertinent to exercise of discretion.
We have reviewed Petitioner’s unpatentability arguments and Patent
Owner’s Preliminary Response, and based on the record before us, we
disagree with Patent Owner that the merits are substantively weak. Prelim.
Resp. 31. In particular, we note that the present record shows that there may
be merit to Petitioner’s scope of enablement challenges. Pet. 44–63; see
also id. at 46, 53–54 (Petitioner contending that disclosure offers relatively
“scarce guidance,” and the only examples provided include
dolastatin/auristatin derivatives).
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Patent Owner, on the other hand, contends that the prior art at the
effective filing date would have allowed a person of ordinary skill in the art
to determine whether an ADC is likely to be cleaved by intracellular
enzymes through assays. Prelim. Resp. 59. These assays would have been
able to demonstrate cleavage inside the cell. Id. at 59–60. Patent Owner
also rebuts Petitioner’s assertion that ADCs are not stable extracellularly,
claiming there were assays available to a person of ordinary skill in the art to
prove that a conjugate would be extracellularly stable. Id. at 61. Patent
Owner further contends that a showing of enablement (1) does not require
complete stability by the ADC and (2) that “the presence of inoperative
embodiments within the scope of a claim does not necessarily render a claim
non-enabled.” Id. at 62 (citing Concert Pharms., Inc. v. Incyte Corp.,
PGR2017-00034, Paper 9 at 12–13 (PTAB Jan. 11, 2018)).
Having reviewed Petitioner’s challenges and Patent Owner’s
preliminary responses, and based on the limited record before us, we do not
find that the merits outweigh the other Fintiv factors favoring exercising our
discretion to deny institution.
7. Conclusion on Discretionary Denial under 35 U.S.C. § 324(a).
Considering all the factors together as a whole, we determine under
the particular circumstances of this case, the interests of efficiency and
integrity of the patent system do favor exercising our discretionary authority
under § 324(a) to deny institution of the Petition.
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III. CONCLUSION
Taking account of the information presented in the Petition, the
Preliminary Response, additional authorized briefing, and the evidence of
record, we exercise our discretion under 35 U.S.C. § 324(a) and deny
institution of post-grant review. Accordingly, the Petition is denied, and no
trial is instituted.
IV. ORDER
Accordingly, it is
ORDERED that the Petition is denied as to all challenged claims, and
no trial is instituted.

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For PETITIONER:
Preston K. Ratliff II
Naveen Modi
Michael A. Stramiello, Ph.D.
Paul Hastings LLP
Daiichi Sankyo-Seagen-PGR-PH@paulhastings.com

David I. Berl
Thomas S. Fletcher
Williams & Connolly LLP
Enhertu@wc.com

For PATENT OWNER:
Matthew I. Kreeger
Parisa Jorjani
Matthew A. Chivis
Morrison & Foerster LLP
SEAGEN-DAIICHI-PGR@mofo.com