                      FOR PUBLICATION

    UNITED STATES COURT OF APPEALS
         FOR THE NINTH CIRCUIT


 JOHN CROWLEY,                                       No. 12-15804
                       Plaintiff-Appellant,
                                                       D.C. No.
                      v.                            2:10-cv-00150-
                                                       KJD-VCF
 ROBERT BANNISTER, DR.; DWIGHT
 NEVEN, Warden; TAMIIA GRISHAM;
 JANE BALAO-CLEDERA; DANIEL                            OPINION
 SUSSMAN; PAT DILIDDO,
             Defendants-Appellees.


         Appeal from the United States District Court
                  for the District of Nevada
          Kent J. Dawson, District Judge, Presiding

                  Argued and Submitted
       September 11, 2013—San Francisco, California

                      Filed October 30, 2013

      Before: Arthur L. Alarcón and Marsha S. Berzon,
      Circuit Judges, and Jack Zouhary, District Judge.*

                    Opinion by Judge Alarcón


 *
   The Honorable Jack Zouhary, District Judge for the U.S. District Court
for the Northern District of Ohio, sitting by designation.
2                    CROWLEY V. BANNISTER

                           SUMMARY**


                      Prisoner Civil Rights

    The panel affirmed in part and vacated in part the district
court’s summary judgment in an action brought under
42 U.S.C. § 1983 by a Nevada state prisoner alleging
deliberate indifference to his medical needs in the
administration of his medication.

    The panel held that plaintiff failed to submit evidence
raising a genuine issue of material fact that his injury could
have been avoided had Dr. Bannister implemented a policy
allowing for the administration of three pill calls per day. The
district court therefore did not err in granting summary
judgment in favor of Dr. Bannister.

    The panel affirmed the district court’s grant of summary
judgment in favor of Warden Neven and nurses Grisham,
Diliddo, and Balao-Cledera because Crowley expressly
waived his appeal against them in his reply brief.

    The panel vacated the clerk’s entry of judgment in favor
of Dr. Sussman because the district court abused its discretion
in failing to comply with Rule 4(m). The panel held that
because the record did not reflect that the district court
provided the required Rule 4(m) notice prior to the clerk’s
entry of judgment in favor of Dr. Sussman, plaintiff was
“precluded from attempting to show good cause” or excusable


  **
     This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
                 CROWLEY V. BANNISTER                      3

neglect for his failure to serve Dr. Sussman in a timely
manner.

    The panel also vacated the district court’s decision
denying plaintiff’s request for leave to amend his second
amended complaint to name additional defendants and to
discover whether any delays on their part in providing
medical treatment caused or exacerbated his Lithium toxicity.
The panel remanded with instructions to comply with Rule
4(m) with respect to Dr. Sussman and to allow plaintiff leave
to amend his second amended complaint.


                        COUNSEL

Francis Gerald Fanning, Tempe, Arizona, for Plaintiff-
Appellant.

Clark G. Leslie, Senior Deputy Attorney General, Office of
the Nevada Attorney General, Appellate Division, Carson
City, Nevada, for Defendants-Appellees.


                        OPINION

ALARCÓN, Senior Circuit Judge:

    John Crowley appeals from the district court’s decision
granting summary judgment and dismissing his pro se claim
that his civil rights were violated because the named
defendants, Dr. Robert Bannister, Dr. Daniel Sussman,
Dwight Neven, Pat Diliddo, Tamiia Grisham, and Jane Balao-
Cledera, were deliberately indifferent to his serious medical
4                  CROWLEY V. BANNISTER

needs, in violation of the Eighth Amendment of the United
States Constitution. Crowley, now represented by counsel,
raises the following issues on appeal: (1) whether we have
jurisdiction to hear this appeal under 28 U.S.C. § 1291;
(2) whether the district court abused its discretion in failing to
comply with Rule 4(m) of the Federal Rules of Civil
Procedure in dismissing the complaint against Dr. Sussman;
(3) whether the district court erred in granting summary
judgment on the merits in favor of Dr. Bannister; (4) whether
the district court abused its discretion in denying his request
for leave to amend his second amended complaint; and
(5) whether the district court should have been required to
advise him of his rights under Rule 56(d) of the Federal Rules
of Civil Procedure.

     We conclude that we have jurisdiction over this appeal.
We affirm the district court’s grant of summary judgment in
favor of Dr. Bannister because Crowley failed to submit
evidence raising a genuine issue of material fact regarding
whether Dr. Bannister was deliberately indifferent to his
serious medical needs. We also affirm the district court’s
grant of summary judgment in favor of Warden Neven and
nurses Grisham, Diliddo, and Balao-Cledera because Crowley
expressly waived his appeal against them in his reply brief.
We vacate the clerk’s entry of judgment in favor of Dr.
Sussman because the district court abused its discretion in
failing to comply with Rule 4(m). We also vacate the district
court’s decision denying Crowley’s request for leave to
amend his second amended complaint to name additional
defendants. We remand with instructions to comply with
Rule 4(m) with respect to Dr. Sussman and to allow Crowley
leave to amend his second amended complaint.
                  CROWLEY V. BANNISTER                       5

                               I

    Crowley, acting pro se, filed his initial complaint in the
district court on February 3, 2010. The district court
dismissed the complaint without prejudice following its initial
review under 28 U.S.C. § 1915A. Crowley then filed his first
amended complaint. Before any action was taken by the
defendants or the district court with respect to the first
amended complaint, he filed a second amended complaint, in
which he alleged a § 1983 action for deliberate indifference
of a serious medical need against Dr. Sussman; Dr. Bannister,
the director of the medical department at the Nevada
Department of Corrections’ (“NDOC”) High Desert State
Prison (“HDSP”); Warden Neven, the warden at HDSP; and
three nurses, Grisham, Diliddo, and Balao-Cledera.

    In his second amended complaint, Crowley set forth the
following allegations: Nurse Grisham was the intake nurse
upon his arrival at HDSP. She informed him there were only
two pill calls at the facility and changed his Lithium
prescription from three doses to two without the prior
approval of a doctor. Dr. Sussman never met with him and
did not properly screen his medical file or review Nurse
Grisham’s alteration to his prescription. His cellmate
informed Nurse Diliddo of his “bizarre behavior” and
unresponsiveness on May 10, 2009, but she refused to treat
him. Nurse Balao-Cledera delayed six hours in providing him
medical care after his cellmate informed her of his behavior
on May 14, 2009, even though she knew he was suffering
from an overdose. Dr. Bannister and Warden Neven were
responsible for the operation of HDSP’s medical unit and
knew that the nurses regularly changed the patient’s
6                  CROWLEY V. BANNISTER

prescriptions, even though they were not qualified to do so
and had not received prior approval from a doctor.

   Crowley claimed that these alleged actions resulted in his
hospitalization and ongoing mental and physical side effects.
He also requested leave to amend the second amended
complaint “with names of Defendants when they are learned.”

    On April 25, 2011, the district court issued a screening
order based on its initial review of the second amended
complaint under 28 U.S.C. § 1915A. It directed Nevada’s
Attorney General to advise the court within 21 days whether
she could accept service for the named defendants. With
respect to any defendant for whom she could not accept
service, the district court ordered her to “file, under seal, the
last known address(es) of those defendant(s);” and also
directed Crowley to “file a motion requesting the issuance of
a summons and specifying a full name and address” for such
defendant. It further ordered that “[s]ervice must be
completed within one hundred twenty (120) days from the
Attorney General’s service of a statement that she will not be
able to accept service for the defendant.”

    Crowley’s copy of the screening order was returned to the
district court as undeliverable on May 2, 2011. The district
court’s docket indicates that the order was “not remailed,” as
“[n]o other address was available” for Crowley at that time.

    Seven days later, on May 9, 2011, Crowley notified the
district court that he was now residing at the Lovelock
Correctional Center (“LCC”). The notice was dated May 6,
2011. The district court docket does not reflect that its
screening order was thereafter mailed to the LCC address.
                  CROWLEY V. BANNISTER                       7

    The Attorney General accepted service on behalf of all
defendants except for Dr. Sussman. She declined to accept
service on behalf of Dr. Sussman because “Daniel Sussman
is not an employee nor has he ever been an employee of the
NDOC.” The Attorney General did not provide Dr.
Sussman’s last known address.

   The Attorney General filed a motion to dismiss the second
amended complaint and, in the alternative, a motion for
summary judgment on behalf of all defendants, except for Dr.
Sussman. In support of the motion, the Attorney General
provided Crowley’s medical records, as well as declarations
from defendants and other NDOC staff.

    Crowley’s medical records reveal the following facts:
Crowley is an inmate who has a history of bipolar disorder,
delusions, Parkinson’s disease, and hypertension. During
Crowley’s initial imprisonment at LCC, he was administered
900 milligrams of Lithium in the morning and afternoon and
600 milligrams of Lithium in the evening. On April 16, 2009,
he was transferred to HDSP. During intake, Nurse Richard
Orden reviewed his chart and referred him to psychological
services. That same day, Dr. Sussman changed Crowley’s
prescription for Lithium to be administered twice daily in
1,200-milligram doses. Although the frequency of the doses
was altered from three to two doses per day, the total daily
amount of 2,400 milligrams stayed the same.

    On May 16, 2009, a floor officer notified the medical staff
regarding Crowley’s unusual behavior. When Nurse Cordero
responded, she was advised by his cellmate that Crowley had
eaten soap the night before and had no appetite for food. She
noted that he was verbally responsive, but was also slow in
8                 CROWLEY V. BANNISTER

his response, confused, staring blankly, jerking, and eating
tissue paper. She determined he should be admitted to the
infirmary and that his Lithium level should be checked.

   Crowley was admitted to the infirmary by the telephone
order of Dr. Holmes. When admitted, he responded to
questions and obeyed simple commands, but was shaking.
His blood was drawn to test his Lithium level.

    Crowley spent the following day in the infirmary and was
attended to by nurses Grisham and Balao-Cledera. Upon
examining Crowley on May 18, a doctor ordered that he be
transferred to the emergency room at Valley Hospital based
on a diagnosis of probable Lithium toxicity. At the hospital,
“he was treated for Lithium toxicity and dehydration
secondary most likely due to Lithium-induced Nephrogenic
Diabetes Insipidus, a concentrating defect which can produce
polyuria, an excessive or abnormally large production and/or
passage of urine.” He was discharged three weeks later.

    Defendants argue that Warden Neven and Dr. Bannister
were not liable under § 1983 because their declarations and
Crowley’s medical records reflected that his medication was
changed by a doctor, not a nurse, and that, even if nurses were
allowed to change a patient’s medications at HDSP, neither
directed, approved, or knew of such a policy. Regarding
nurses Grisham, Diliddo, and Balao-Cledera, Defendants
argue that the medical records and other evidence established
that Crowley had incorrectly identified their roles in his
medical care and that the medical care they did provide
Crowley did not reflect willful indifference.
                  CROWLEY V. BANNISTER                       9

    The district court issued a minute order informing
Crowley of his rights under Rules 12 and 56 of the Federal
Rules of Civil Procedure, as required by this Court’s
decisions in Klingele v. Eikenberry, 849 F.2d 409 (9th Cir.
1988), and Rand v. Rowland, 154 F.3d 952 (9th Cir. 1998) (en
banc). The court’s order advised Crowley, inter alia, that “if
evidence is submitted with a motion to dismiss and
considered by the court, then the motion will be treated as a
motion for summary judgment” and that “if the court grants
summary judgment, then judgment may be entered against
[him] and this lawsuit will end without trial.” In addition, it
instructed Crowley that to oppose a motion for summary
judgment:

       [He] must set out specific facts in the form of
       admissible evidence (such as affidavits,
       declarations, depositions, answers to
       interrogatories, or properly authenticated
       documents as provided in Rule 56(e)), that
       contradict the facts shown in the defendant’s
       declarations and documents and show that
       there is a genuine issue of fact for trial.

     Crowley opposed the motion for summary judgment,
contending that “[e]ven if his recollection of who did what on
what day is impaired, the facts remain that he suffered severe
lithium toxicity and he had to be hospitalized.” He did not
submit any evidence in support of his opposition. Instead, he
requested the opportunity to amend any issue the district court
deemed unclear or in dispute.

    The district court granted summary judgment with respect
to all defendants, except for Dr. Sussman. It concluded that
10                CROWLEY V. BANNISTER

Crowley failed to produce any admissible evidence raising a
genuine issue of material fact that Dr. Bannister knew of the
alleged constitutional violations. Regarding his claims
against nurses Grisham, Diliddo, and Balao-Cledera, it
concluded that Crowley failed to raise a genuine issue of
material fact regarding their alleged liability because the
“uncontroverted evidence” and “undisputed facts” reflected
that he had improperly identified them in his second amended
complaint as the persons responsible for a deliberate
indifference to his serious medical needs, and that the level of
care they did provide him, as evidenced by the medical
records, “cannot state a claim for deliberate indifference to
[Crowley’s] serious medical needs.” With respect to all
defendants, except for Dr. Sussman who was not a party to
the motion, the district court also concluded, alternatively,
that these defendants were entitled to qualified immunity
because there was no clearly established law that would have
put them on notice that their conduct was unlawful.

    The same day the district court issued its order granting
summary judgment in favor of Dr. Bannister, Warden Neven,
and nurses Diliddo, Grisham, and Balao-Cledera, the clerk
entered judgment also dismissing this action against Dr.
Sussman. Crowley timely appealed. In addition to filing his
notice of appeal, Crowley lodged a proposed third amended
complaint against Dr. Bannister, Dr. Holmes, Ms. Walsh, and
nurses Orden and Cordero.

                               II

    Represented by counsel on appeal, Crowley argues that
the district court erred in granting summary judgment because
(1) “the evidence would allow a reasonable jury to conclude
                  CROWLEY V. BANNISTER                       11

that [Dr. Sussman and Dr. Bannister] acted with deliberate
indifference to [his] medical needs,” (2) the district court
abused its discretion in denying his request for leave to amend
his second amended complaint, and (3) the district court
failed to advise him that he could request that it defer
considering defendants’ motions until after discovery. He
expressly waived any challenge to the district court’s grant of
summary judgment in favor of Warden Neven and nurses
Diliddo, Grisham, and Balao-Cledera in his reply brief.

                               A

    Crowley filed a timely notice of appeal. We have
jurisdiction to review final decisions of the district court
under 28 U.S.C. § 1291. Neither party addressed our
jurisdiction in view of the fact that the district court granted
summary judgment to fewer than all the named defendants.
Nor did the parties address whether a district court is
empowered to enter judgment against a party that was never
served. Because we are required to raise issues concerning
our appellate jurisdiction sua sponte, United States ex rel.
Shutt v. Cmty. Home & Health Care Servs., Inc., 550 F.3d
764, 766 (9th Cir. 2008), we asked the parties to file
supplemental briefs regarding our jurisdiction to hear this
appeal. In response to our request, Crowley now asks that we
dismiss his appeal and remand because the district court’s
decision was not final for purposes of conferring jurisdiction
under 28 U.S.C. § 1291. We disagree.

    “If an action is dismissed as to all of the defendants who
have been served and only unserved defendants remain, the
district court’s order may be considered final under Section
1291 for the purpose of perfecting an appeal.” Patchick v.
12                CROWLEY V. BANNISTER

Kensington Publ’g Corp., 743 F.2d 675, 677 (9th Cir. 1984)
(per curiam). This Court has recognized a limited exception
where “it is clear from the course of proceedings that further
adjudication is contemplated.” Disabled Rights Action
Comm. v. Las Vegas Events, Inc., 375 F.3d 861, 872 (9th Cir.
2004).

    In Patchick, 743 F.2d at 676, the district court granted a
dismissal requested by some, but not all defendants. Because
plaintiff had attempted to serve the remaining defendants and
had not conceded that service was improper, this Court
dismissed the appeal for lack of jurisdiction, holding that
“[t]he action cannot be final until the service dispute is
resolved by the district court in favor of [those] defendants or
until the action is dismissed as to those defendants.” Id. at
677.

    The district court’s order granted summary judgment in
favor of the defendants who had been served, and the parties
do not dispute that the only remaining defendant, Dr.
Sussman, was never served. Nothing in the district court’s
order suggests that further adjudication was contemplated,
and the clerk entered judgment in favor of all defendants that
same day, finally disposing of the action against all
defendants. See Nat’l Distrib. Agency v. Nationwide Mut. Ins.
Co., 117 F.3d 432, 434 (9th Cir. 1997) (“Had the court
entered a separate final judgment subsequent to the dismissal
order, we would be confident the court intended no further
action in this case.”). Crowley’s subsequent lodging of a
proposed third amended complaint occurred at the same time
that he filed a notice of appeal; he did not name Dr. Sussman
as a defendant in that complaint. We are persuaded that we
have jurisdiction to review this appeal.
                  CROWLEY V. BANNISTER                      13

                              B

    Even though the district court’s grant of summary
judgment was a final order, we cannot reach the merits of
Crowley’s claims against Dr. Sussman, as he was never
served with the complaint and summons. “‘A federal court is
without personal jurisdiction over a defendant unless the
defendant has been served in accordance with Fed. R. Civ. P.
4.’” Travelers Cas. & Sur. Co. of Am. v. Brenneke, 551 F.3d
1132, 1135 (9th Cir. 2009) (quoting Benny v. Pipes, 799 F.2d
489, 492 (9th Cir. 1986)). “[W]hether personal jurisdiction
can be exercised is a question of law reviewable de novo
when the underlying facts are undisputed.” Id. (citing FDIC
v. British-Am. Ins. Co., 828 F.2d 1439, 1441 (9th Cir. 1987)).

    “‘Rule 4 is a flexible rule that should be liberally
construed so long as a party receives sufficient notice of the
complaint.’” Benny, 799 F.2d at 492 (quoting United Food &
Commercial Workers Union v. Alpha Beta Co., 736 F.2d
1371, 1382 (9th Cir. 1984)). However, “[n]either actual
notice, nor simply naming the person in the caption of the
complaint, will subject defendants to personal jurisdiction if
service was not made in substantial compliance with Rule 4.”
Jackson v. Hayakawa, 682 F.2d 1344, 1347 (9th Cir. 1982)
(internal citations omitted).

    The parties do not dispute that Crowley failed to serve Dr.
Sussman; therefore, the district court lacked personal
jurisdiction over Dr. Sussman and should have proceeded
under Rule 4(m) to dismiss the complaint against Dr.
Sussman without prejudice. Rule 4(m) provides that:
14                 CROWLEY V. BANNISTER

        If a defendant is not served within 120 days
        after the complaint is filed, the court—on
        motion or on its own after notice to the
        plaintiff—must dismiss the action without
        prejudice against that defendant or order that
        service be made within a specified time. But
        if the plaintiff shows good cause for the
        failure, the court must extend the time for
        service for an appropriate period.

Fed. R. Civ. P. 4(m) (emphasis added). “As indicated by the
plain language of Rule 4(m), notice to the plaintiff must be
given prior to sua sponte dismissal.” Thompson v.
Maldonado, 309 F.3d 107, 110 (2d Cir. 2002) (per curiam).
“[A] district court abuses its discretion when . . . it dismisses
a complaint sua sponte for lack of service without first giving
notice to the plaintiff and providing an opportunity for [him]
to show good cause for the failure to effect timely service.”
Meilleur v. Strong, 682 F.3d 56, 61 (2d Cir.) (citing Famous
Horse Inc. v. 5th Ave. Photo Inc., 624 F.3d 106, 115 (2d Cir.
2010)), cert. denied, 133 S. Ct. 655 (2012).

    The Seventh Circuit analyzed Rule 4(m) in Brengettcy v.
Horton, 423 F.3d 674, 683 (7th Cir. 2005). In that matter, the
district court dismissed on its own motion plaintiff’s claims
against certain defendants for failure to perfect service
consistent with Rule 4. Id. On appeal, the Seventh Circuit
held that the district court erred because it did not “giv[e the
plaintiff] notice, an opportunity to show good cause, and an
opportunity to request an extension of time . . . .” Id. It
remanded to the district court with instructions to reinstate the
plaintiff’s suit allowing plaintiff “an opportunity to show
either that there was good cause to explain his earlier failure
                      CROWLEY V. BANNISTER                              15

to effect service or that he is otherwise entitled to an
extension of time.” Id.

    In its April 25, 2011, screening order, the district court
instructed Crowley to complete service within 120 days from
the Attorney General’s service of a statement that she would
not be able to accept service for a defendant. The parties
dispute whether Crowley received this order. The district
court’s docket indicates that the notice was “[r]eturned as
[u]ndeliverable” and was “not remailed,” as “[n]o other
address [was] available.” No further entries appear on the
docket to reflect whether the order was resent to Crowley
after he advised the district court of his new address the
following week.1

    Because the record does not reflect that the district court
provided the required Rule 4(m) notice prior to the clerk’s
entry of judgment in favor of Dr. Sussman, plaintiff was
“precluded from attempting to show good cause” or excusable
neglect for his failure to serve Dr. Sussman in a timely
manner. Thompson, 309 F.3d at 110. This Court has
explained that



   1
      In a letter submitted after oral argument, the Attorney General
maintains that the order was resent to Crowley’s correct address on May
10, 2011, and points to an alleged “note” on the district court’s docket in
support of his contention. This note does not appear in the public docket;
nor does it appear in the record. Because this unsworn factual statement
is not properly before us, we cannot consider it. Barcamerica Int’l USA
Trust v. Tyfield Imps., Inc., 289 F.3d 589, 593 n.4 (9th Cir. 2002) (holding
that “arguments and statements of counsel ‘are not evidence . . . .’”
(quoting Smith v. Mack Trucks, 505 F.2d 1248, 1249 (9th Cir. 1974) (per
curiam))).
16                CROWLEY V. BANNISTER

       Rule 4(m) provides two avenues for relief.
       The first is mandatory: the district court must
       extend time for service upon a showing of
       good cause. The second is discretionary: if
       good cause is not established, the district court
       may extend time for service upon a showing
       of excusable neglect. Exercise of discretion to
       extend time to complete service is appropriate
       when, for example, a statute-of-limitations bar
       would operate to prevent re-filing of the
       action.

Lemoge v. United States, 587 F.3d 1188, 1198 (9th Cir. 2009)
(internal citations omitted). The Attorney General concedes
Crowley may have had valid grounds for requesting an
extension of the time to serve Dr. Sussman under Rule 4(m)
because the statute of limitations “ran on or about May 18,
2011—the same day the [Notice of Acceptance of Service]
was sent to Crowley.” The district court abused its discretion
in failing to provide Crowley with the opportunity to show
good cause or excusable neglect. In addition, the clerk also
violated Rule 4(m) by entering judgment in favor of Dr.
Sussman when it should have dismissed the complaint against
him without prejudice.

   In view of the district court’s failure to comply with Rule
4(m), we vacate the entry of judgment in favor of Dr.
Sussman and remand for further proceedings.

                              C

    The district court granted summary judgment in favor of
Dr. Bannister because Crowley failed to produce evidence
                   CROWLEY V. BANNISTER                       17

raising a genuine issue of material fact that Dr. Bannister
knew of the alleged constitutional violations. Crowley does
not contest this determination on appeal, but instead argues
that Dr. Bannister is liable as a supervisor because he was in
charge of implementing a drug distribution policy that
resulted in harm. He argues that Dr. Bannister “adhere[d] to
a ‘two pill call’ policy” despite the medical risks.

    Even though the district court did not consider this theory
of liability in its order, “[w]e may affirm on any ground
present in the record.” O’Guinn v. Lovelock Corr. Ctr.,
502 F.3d 1056, 1059 (9th Cir. 2007) (citing In re Harbin,
486 F.3d 510, 520 (9th Cir. 2007)). “We review a grant of
summary judgment de novo and must determine, viewing the
facts in the light most favorable to the nonmoving party,
whether there are any genuine issues of material fact and
whether the district court correctly applied the relevant
substantive law.” Snow v. McDaniel, 681 F.3d 978, 985 (9th
Cir. 2012) (citing Lopez v. Smith, 203 F.3d 1122, 1131 (9th
Cir. 2000) (en banc)).

    “‘Under Section 1983, supervisory officials are not liable
for actions of subordinates on any theory of vicarious
liability.’” Id. at 989 (quoting Hansen v. Black, 885 F.2d 642,
645–46 (9th Cir. 1989)). “A supervisor may be liable only if
(1) he or she is personally involved in the constitutional
deprivation, or (2) there is ‘a sufficient causal connection
between the supervisor’s wrongful conduct and the
constitutional violation.’” Id. (quoting Hansen, 885 F.2d at
646). Under the latter theory, “[s]upervisory liability exists
even without overt personal participation in the offensive act
if supervisory officials implement a policy so deficient that
the policy ‘itself is a repudiation of constitutional rights’ and
18                CROWLEY V. BANNISTER

is ‘the moving force of a constitutional violation.’” Hansen,
885 F.2d at 646 (quoting Thompkins v. Belt, 828 F.2d 298,
304 (5th Cir. 1987)).

    Crowley failed to raise a genuine issue of material fact as
to causation. See OSU Student Alliance v. Ray, 699 F.3d
1053, 1076 (9th Cir. 2012) (“Advancing a policy that requires
subordinates to commit constitutional violations is always
enough for § 1983 liability . . . so long as the policy
proximately causes the harm—that is, so long as the
plaintiff’s constitutional injury in fact occurs pursuant to the
policy.”), cert. denied, No. 12-1296, 2013 WL 1808554 (Oct.
7, 2013). Dr. Bannister’s declaration states that the change in
dosage had either no effect or benefitted Crowley and that his
Lithium toxicity was attributable to other causes, likely
dehydration resulting from polyuria or his diet. Crowley
presented no evidence that the change from three to two daily
doses, without increasing the total amount of Lithium
prescribed, could have caused his Lithium toxicity.

     In view of Dr. Bannister’s uncontradicted declaration,
Crowley has failed to raise a genuine issue of material fact
that his injury could have been avoided had Dr. Bannister
implemented a policy allowing for the administration of three
pill calls per day. The district court did not err in granting
summary judgment in favor of Dr. Bannister.

                               D

    Crowley contends further that the district court should
have granted him leave to amend his second amended
complaint because his failure to identify the correct
defendants was understandable based on his incapacitation at
                  CROWLEY V. BANNISTER                       19

the time of the incident. He requested leave to amend in his
second amended complaint and in his opposition to the
Attorney General’s motions.

    Even though the district court did not expressly rule on
Crowley’s requests, its order granting summary judgment
“necessarily entailed a denial of the alternative request for
leave to amend and a determination . . . ‘that the pleading
could not possibly be cured by the allegation of other facts.’”
Knevelbaard Dairies v. Kraft Foods, Inc., 232 F.3d 979, 983
(9th Cir. 2000) (quoting Lopez, 203 F.3d at 1127). We
review for abuse of discretion the denial of a motion to amend
the complaint. Hall v. City of Los Angeles, 697 F.3d 1059,
1072 (9th Cir. 2012).

    “Federal Rule of Civil Procedure 15(a) provides that a
party may amend its pleading once as a matter of course
within certain time limits, or, in all other instances, with the
court’s leave.” Id. (citing Fed. R. Civ. P. 15(a)). “‘[L]eave to
amend should be granted if it appears at all possible that the
plaintiff can correct the defect.’” Lopez, 203 F.3d at 1130
(emphasis added) (quoting Balistreri v. Pacifica Police Dep’t,
901 F.2d 696, 701 (9th Cir. 1990)). “[T]he ‘rule favoring
liberality in amendments to pleadings is particularly important
for the pro se litigant. Presumably unskilled in the law, the
pro se litigant is far more prone to make errors in pleading
than the person who benefits from the representation of
counsel.’” Id. at 1131 (quoting Noll v. Carlson, 809 F.2d
1446, 1448 (9th Cir. 1987)).

   A district court abuses its discretion by denying leave to
amend where the complaint’s deficiencies could be cured by
naming the correct defendant. See, e.g., id. at 1130–31
20                CROWLEY V. BANNISTER

(complaint named the wrong defendant); Lucas v. Dep’t of
Corr., 66 F.3d 245, 248–49 (9th Cir. 1995) (complaint failed
to name individual defendants). If the identity of any
defendant is unknown, “the plaintiff should be given an
opportunity through discovery to identify the unknown
defendants, unless it is clear that discovery would not uncover
the identities, or that the complaint would be dismissed on
other grounds.” Gillespie v. Civiletti, 629 F.2d 637, 642 (9th
Cir. 1980).

    Crowley also alleged that his cellmate requested medical
assistance on his behalf on May 10, 2009, but that Nurse
Diliddo ignored the request and refused to treat him; and that
his cellmate again requested medical assistance several days
later on May 14, but that he had to wait six hours after Nurse
Balao-Cledera responded to the request before he was
admitted to the infirmary. Crowley misidentified nurses
Diliddo and Balao-Cledera as responsible for this conduct.
The medical records show that Nurse Cordero was the nurse
who responded to a cellmate’s request on May 16, the day he
was actually admitted to the infirmary. The present record
does not identify the individual who allegedly failed to
respond on May 10.

    “A prison official violates the Eighth Amendment when
he acts with ‘deliberate indifference’ to the serious medical
needs of an inmate.” Snow, 681 F.3d at 985 (quoting Farmer
v. Brennan, 511 U.S. 825, 828 (1994)). “Indifference ‘may
appear when prison officials deny, delay or intentionally
interfere with medical treatment, or it may be shown by the
way in which prison officials provide medical care.’” Jett v.
Penner, 439 F.3d 1091, 1096 (9th Cir. 2006) (quoting
McGuckin v. Smith, 974 F.2d 1050, 1059 (9th Cir. 1992),
                   CROWLEY V. BANNISTER                       21

overruled on other grounds by WMX Techs., Inc. v. Miller,
104 F.3d 1133 (9th Cir. 1997) (en banc)).

    We conclude that the district court abused its discretion in
denying Crowley leave to amend his second amended
complaint to name the correct defendants and to discover
whether any delays on their part in providing medical
treatment caused or exacerbated his Lithium toxicity
constituting indifference to his medical needs.

                               E

     The district court issued a notice to Crowley pursuant to
Klingele and Rand. Crowley concedes that the notice he
received complies with the law of this Circuit. He invites us,
however, to expand the required notice to advise pro se
litigants of their right under Rule 56(d) to seek additional time
to conduct discovery before facing a dispositive motion.

    This Court adopted the notice requirement because “it
effectuates the purpose of the Federal Rules to eliminate
‘procedural booby traps’ which could prevent
‘unsophisticated litigants from ever having their day in
court.’” Rand, 154 F.3d at 958–59 (quoting Surowitz v.
Hilton Hotels Corp., 383 U.S. 363, 373 (1966)). Under the
law of this Circuit, where, as here, a plaintiff does not know
the identity of a defendant prior to the filing of a complaint,
he “should be given an opportunity through discovery to
identify the unknown defendants . . . .” Gillespie, 629 F.2d at
642. Accordingly, Crowley will have the opportunity on
remand to attempt to name the proper parties, after any
discovery opportunity the district court permits. We decline
22                    CROWLEY V. BANNISTER

Crowley’s invitation to expand the required contents of the
notice to pro se litigants at this time.2

                             CONCLUSION

    We vacate and remand the entry of judgment in favor of
Dr. Sussman because the district court failed to comply with
Rule 4(m), and we also vacate and remand its denial of
Crowley’s request for leave to amend. We affirm the district
court’s grant of summary judgment in favor of Dr. Bannister,
Warden Neven, and nurses Grisham, Diliddo, and Balao-
Cledera.

  VACATED               in    part;      AFFIRMED            in     part;
REMANDED.

  EACH PARTY SHALL BEAR ITS OWN COSTS ON
APPEAL.




  2
    We decline at present to require an expansion of the Rand/Klingele
notice. However, district courts could be well served by refraining from
converting motions to dismiss into motions for summary judgment, or,
when doing so, advising pro se plaintiffs of their rights under Rule 56(d).
