Williams v. Costco Wholesale Corp., 471 F.3d 975 (9th Cir. 2006). · Go Syfert
Williams v. Costco Wholesale Corp., 471 F.3d 975 (9th Cir. 2006). Cases Citing This Book View Copy Cite
129 citation events (129 in the last 25 years) across 20 distinct courts.
Strongest positive: Claudio Lopez v. Vestis Services, LLC (cacd, 2025-06-06)
Treatment trajectory · 2006 → 2026 · click a year to view as-of
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Top citers, strongest first. 50 distinct citers. How cited ↗
discussed Cited as authority (verbatim quote) Claudio Lopez v. Vestis Services, LLC (2×) also: Cited "see, e.g."
C.D. Cal. · 2025 · signal: see · quote attribution · 1 verbatim quote · confidence high
he propriety of removal is determined solely on the basis of the pleadings filed in state court.
examined Cited as authority (verbatim quote) Nationwide Agribusiness Insurance Company v. Penn-Star Insurance Company
E.D. Cal. · 2024 · quote attribution · 1 verbatim quote · confidence high
we have long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.
examined Cited as authority (verbatim quote) Artem Karapetyan v. BMW Financial Services NA, LLC
C.D. Cal. · 2024 · signal: see, e.g. · quote attribution · 1 verbatim quote · confidence high
we have long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.
examined Cited as authority (verbatim quote) Alina Sokiazian v. BMW Financial Services NA, LLC
C.D. Cal. · 2024 · signal: see, e.g. · quote attribution · 1 verbatim quote · confidence high
we have long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.
examined Cited as authority (verbatim quote) Fifteen Twenty-One Second Avenue Condominium Association v. Viracon LLC
W.D. Wash. · 2024 · signal: see · quote attribution · 1 verbatim quote · confidence high
courts have long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.
discussed Cited as authority (verbatim quote) Katchatag v. State of Alaska
D. Alaska · 2024 · signal: see also · quote attribution · 1 verbatim quote · confidence high
we have long held that post-removal amendments to the pleadings cannot effect whether a case is removable
discussed Cited as authority (verbatim quote) Annette Cody v. P.C. Richard and Son Service Company, Inc.
C.D. Cal. · 2023 · signal: see also · quote attribution · 1 verbatim quote · confidence high
we have long held that post-removal amendments to the pleadings 16 cannot effect whether a case is removable
examined Cited as authority (verbatim quote) Washington State Nurses Association v. MultiCare Health Systems
W.D. Wash. · 2022 · signal: see, e.g. · quote attribution · 1 verbatim quote · confidence high
we 15 have long held that post-removal amendments to the pleadings cannot affect whether a case is 16 removable, because the propriety of removal is determined solely on the basis of the pleadings 17 filed in state court.
examined Cited as authority (verbatim quote) Washington State Nurses Association v. MultiCare Health Systems
W.D. Wash. · 2022 · signal: see, e.g. · quote attribution · 1 verbatim quote · confidence high
we 15 have long held that post-removal amendments to the pleadings cannot affect whether a case is 16 removable, because the propriety of removal is determined solely on the basis of the pleadings 17 filed in state court.
discussed Cited as authority (verbatim quote) Robert Wayne Ives v. Allstate Northbrook Indemnity Company
C.D. Cal. · 2020 · signal: see · quote attribution · 1 verbatim quote · confidence high
post-removal amendments to the pleadings 16 cannot affect whether a case is removable, because the propriety of removal is 17 determined solely on the basis of the pleadings filed in state court.
discussed Cited as authority (verbatim quote) Eileen Laub v. Kao USA Inc.
C.D. Cal. · 2020 · signal: see · quote attribution · 1 verbatim quote · confidence high
jurisdiction must be analyzed on the basis of the pleadings filed at the time of removal
examined Cited as authority (verbatim quote) Barefield v. HSBC Holdings PLC (2×) also: Cited as authority (quoted)
E.D. Cal. · 2018 · quote attribution · 2 verbatim quotes · confidence high
we have long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.
discussed Cited as authority (verbatim quote) US Mortgage, Inc. v. Saxton
9th Cir. · 2007 · signal: see · quote attribution · 1 verbatim quote · confidence high
the propriety of removal is determined solely on the basis of the pleadings filed in state court
discussed Cited as authority (quoted) Glen Matthews v. Specialized Loan Servicing, LLC
C.D. Cal. · 2020 · signal: see · quote attribution · 1 verbatim quote · confidence high
any post-removal pleadings must be treated just as they would be in a case originally 27 filed in federal court.
discussed Cited as authority (quoted) Czapla v. Republic Servs., Inc.
E.D. Mo. · 2019 · quote attribution · 1 verbatim quote · confidence low
once a case has been properly removed, the district court has jurisdiction over it on all grounds apparent from the complaint, not just those cited in the removal notice.
discussed Cited as authority (rule) Jane Doe v. Fox Corporation et al
C.D. Cal. · 2025 · confidence medium
Any post-removal pleadings must be treated just as they would be in a case originally filed in federal court.” Williams, 471 F.3d at 977; see also Royal Canin U. S. A., Inc. v. Wullschleger, 604 U.S. 22 , 22—23 (2025) (“[C]ourts look to the amended complaint to determine jurisdiction.”).
discussed Cited as authority (rule) Pawl Washeleski v. City of Campbell (2×) also: Cited "see, e.g."
N.D. Cal. · 2025 · confidence medium
The City is correct that the Ninth Circuit previously held that “post-removal amendments 8 || to the pleadings cannot affect whether a case is removable.” Williams, 471 F.3d at 976.
cited Cited as authority (rule) Gregory O’Neal v. Tanimura & Antle Fresh Foods, Inc.; City of Yuma
D. Ariz. · 2025 · confidence medium
Doc. 16 at 5-6 (citing Williams v. 15 Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006)).
discussed Cited as authority (rule) Silva v. Kaiser Foundation Hospitals
E.D. Cal. · 2025 · confidence medium
Thus, while the Ninth Circuit has “long held that post-removal 7 amendments to the pleadings cannot affect whether a case is removable,” Williams v. 8 Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006) (citations omitted), if a 9 plaintiff files an amended complaint that excises any federal law claims, the court may 10 not exercise supplemental jurisdiction over the state law claims.
cited Cited as authority (rule) Silvia Patricia Hercules v. Costco Wholesale Corporation
C.D. Cal. · 2025 · confidence medium
Khachatrvan, 2024 WL 923027 at *1; Williams, 471 F.3d at 976-77.
discussed Cited as authority (rule) Khlafa v. Oregon Health And Science University
D. Or. · 2025 · confidence medium
The Ninth Circuit has “long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006). “[W]hen a defendant removes a case to federal court based on the presence of a federal claim, an amendment eliminating the original basis for federal jurisdiction generally does not defeat jurisdiction.” Rockwell Intern.
discussed Cited as authority (rule) Roberts v. IFS Topco, LLC
S.D. Cal. · 2025 · confidence medium
Courts 22 determine removal jurisdiction based on the operative complaint at the time of removal. 23 As the Ninth Circuit held in Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th 24 Cir. 2006), post-removal amendments do not affect removability.
discussed Cited as authority (rule) Fondren v. I Got My Chance L L C
W.D. La. · 2025 · confidence medium
In another case cited by Canal, Williams v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006), remand after dismissal of federal question claims was said to be erroneous because “[o]nce a case has been properly removed, the district court has jurisdiction over it on all grounds apparent from the complaint, not just those cited in the removal notice.” (Emphasis added).
discussed Cited as authority (rule) Donald Guilford v. APM Terminals Pacific LLC
C.D. Cal. · 2024 · confidence medium
Defendants argue that the post-removal FAC does not affect surisdiction because the United States Court of Appeals for the Ninth Circuit (“the Ninth Circuit”) has “long held that ‘post-removal amendments to the UNITED STATES DISTRICT COURT CENTRAL DISTRICT OF CALIFORNIA CIVIL MINUTES — GENERAL ‘O° JS-6 Case No. 2:24-cv-05307-CAS-JCx Date September 30, 2024 Title Donald Guilford v. APM Terminals Pacific LLC et al pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.’” Id. (q…
discussed Cited as authority (rule) (PC) Foster v. Baker
E.D. Cal. · 2024 · confidence medium
Williams v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006). 17 A district court “may decline to exercise supplemental jurisdiction . . . [if] the district 18 court has dismissed all claims over which it has original jurisdiction.” 28 U.S.C. § 1367 (c)(3); 19 see also Acri v. Varian Assocs., Inc., 114 F.3d 999 , 1001 n.3 (9th Cir. 1997) (en banc) 20 (explaining that a district court may decide sua sponte to decline to exercise supplemental 21 jurisdiction). 22 ii.
discussed Cited as authority (rule) Robert Reed v. Thor Industries, Inc. (2×) also: Cited "see"
C.D. Cal. · 2024 · confidence medium
However, “where the district court is presented with a case within its original jurisdiction, it has a ‘virtually unflagging obligation’ to exercise the jurisdiction conferred upon it by the coordinate branches of government and duly invoked by litigants.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006) (cleaned up).
discussed Cited as authority (rule) Kaiser v. Wells Fargo Clearing Services, LLC
D. Nev. · 2024 · confidence medium
The Ninth 13 Circuit has held that “[o]nce a case has been properly removed, the district court has 14 jurisdiction over it on all grounds apparent from the complaint, not just those cited in the 15 removal notice.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006) (citing 16 Brockman v. Merabank, 40 F.3d 1013, 1016 (9th Cir. 1994)).
discussed Cited as authority (rule) John Ketch LLC v. San Juan County
W.D. Wash. · 2024 · confidence medium
Williams 4 v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006) (quoting United States v. Rubenstein, 5 971 F.2d 288, 293 (9th Cir. 1992) (cleaned up)).
discussed Cited as authority (rule) Evans v. Jacobs Solutions Inc
W.D. Wash. · 2024 · confidence medium
Williams v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 22 2006) (quoting United States v. Rubenstein, 971 F.2d 288, 293 (9th Cir. 1992) (alteration in 23 original) (internal quotation marks omitted)). 24 1 Here, Defendants Jacobs Solutions Inc. and CH2M HILL, Inc. have invoked the Court’s 2 jurisdiction under 28 U.S.C. § 1332 (d).
discussed Cited as authority (rule) Spencer v. PeaceHealth
W.D. Wash. · 2024 · confidence medium
Analysis 18 The Court must assess PeaceHealth’s preemption arguments based on Ms. Spencer’s 19 original complaint. “[P]ost-removal amendments to the pleadings cannot affect whether a case is 20 removable, because the propriety of removal is determined solely on the basis of the pleadings 21 filed in state court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006). 22 PeaceHealth contends Ms. Spencer’s complaint is “predicated on rights created by the 23 CBA” and “‘substantially dependent’ on the interpretation of the CBA.” (Reply at 5.) Ms. 1 Spencer co…
discussed Cited as authority (rule) Crippen v. International Paper Co.
E.D. Cal. · 2024 · confidence medium
No. 18 20 at 3.) IPC’s argument is based on Ninth Circuit precedent holding that for federal question 21 jurisdiction, “the propriety of removal is determined solely on the basis of the pleadings filed in 22 state court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006) (citing 23 Sparta Surgical Corp. v. Nat’l Ass’n of Sec.
discussed Cited as authority (rule) CHOMKA v. Walgreen Co.
N.D. Cal. · 2024 · confidence medium
The motion to remand is denied. 3 “The propriety of removal is determined solely on the basis of the pleadings filed in state 4 court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006).
discussed Cited as authority (rule) Perez v. Foster Poultry Farms
E.D. Cal. · 2024 · confidence medium
Williams 16 v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006). 17 A state court action is within the Court’s original subject matter jurisdiction if either plaintiff and 18 defendant are diverse in citizenship and the amount in controversy exceeds $75,000 (diversity 19 jurisdiction); or the state court action presents a federal question (federal question jurisdiction). 28 20 U.S.C. §§ 1331 , 1332.
discussed Cited as authority (rule) Nelson v. Foster Poultry Farms
E.D. Cal. · 2023 · confidence medium
Once a case has been properly removed, the district court has 8 jurisdiction over it on all grounds apparent from the complaint, not just those cited in the removal notice. 9 Williams v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006). 10 D.
discussed Cited as authority (rule) Shawn L. Quinney v. City of Santa Monica
C.D. Cal. · 2023 · confidence medium
As an initial matter, “post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006) (per curiam).
cited Cited as authority (rule) Maria Martha Alvarado v. Vie De France Yamazaki, Inc.
C.D. Cal. · 2022 · confidence medium
Cal. Jul. 15, 2021) (citing Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006). // 1 Yamazaki, Inc. filed an identical Request for Judicial Notice in both cases.
cited Cited as authority (rule) Alex Hernandez v. Vie De France Yamazaki, Inc.et al
C.D. Cal. · 2022 · confidence medium
Cal. Jul. 15, 2021) (citing Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006). // 1 Yamazaki, Inc. filed an identical Request for Judicial Notice in both cases.
discussed Cited as authority (rule) Reynolds v. Singh
E.D. Cal. · 2022 · confidence medium
Opp’n at 9-12. 4 Relying on Williams v. Costco Wholesale Corp., 471 F.3d 975 (9th 5 Cir. 2006), Defendant contends that “since Defendant Singh 6 removed this matter on the basis of federal question 7 jurisdiction, this court retains jurisdiction on that basis, as 8 well as any other basis for jurisdiction apparent in the 9 complaint, including diversity jurisdiction.” Opp’n at 10. 10 This argument is meritless. 11 In Williams the Ninth Circuit held that “[o]nce a case has 12 been properly removed, the district court has jurisdiction over 13 it on all grounds apparent from the complai…
discussed Cited as authority (rule) Hrones v. Rideout Memorial Hospital
E.D. Cal. · 2022 · confidence medium
But this court would have jurisdiction over the action “on all grounds apparent from 15 the complaint, not just those cited in the removal notice.” Williams v. Costco Wholesale Corp., 16 471 F.3d 975, 977 (9th Cir. 2006) (per curiam).
discussed Cited as authority (rule) Whitehurst v. Dollar Tree Stores, Inc.
E.D. Cal. · 2022 · confidence medium
Dealers, Inc., 159 F.3d 1209 , 27 | 1213 (9th Cir. 1998). “[P]ost-removal amendments to the pleadings cannot affect whether a case 28 | is removable, because the propriety of removal is determined solely on the basis of the pleadings 1 filed in state court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006).
discussed Cited as authority (rule) EHC Aspen Properties, LLC v. CCUR Holdings, Inc.
C.D. Cal. · 2021 · confidence medium
LEGAL STANDARD 10 11 While a court retains subject-matter jurisdiction despite “post-removal 12 amendments to the pleadings” because “whether a case is removable . . . is determined 13 solely on the basis of the pleadings filed in state court,” Williams v. Costco Wholesale 14 Corp., 471 F.3d 975, 976 (9th Cir. 2006) (per curiam), a court’s exercise of supplemental 15 jurisdiction over remaining state law claims is discretionary, Horne v. Wells Fargo Bank, 16 N.A., 969 F. Supp. 2d 1203, 1209-10 (C.D.
discussed Cited as authority (rule) Iconic Medical Group LLC v. Lonahte Holdings LLC
D. Colo. · 2021 · confidence medium
As a result, Ring-Neck may not, through a response to a motion to remand, attempt to add a new basis for the Court’s jurisdiction that was not asserted at the time of removal or within the thirty day window for removal. 4 Ring-Neck argues that Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006), stands for the proposition that, as long as there is “another valid cause for removal,” a court should not remand the case.
discussed Cited as authority (rule) Zuniga v. Safeway, Inc.
N.D. Cal. · 2021 · confidence medium
Under Grable, a federal court has jurisdiction over claims asserted under state law 19 “that nonetheless turn on substantial questions of federal law, and thus justify resort to the 20 experience, solicitude, and hope of uniformity that a federal forum offers on federal issues.” 21 Grable, 545 U.S. at 312 . “[F]ederal jurisdiction over a state law claim will lie if a federal issue is: 22 3 While post-removal amendments may not be used to avoid federal question jurisdiction or 23 proper removal, see Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir.2006), a 24 court’s conti…
discussed Cited as authority (rule) Zeto v. BMW of North America, LLC (2×)
S.D. Cal. · 2020 · confidence medium
Accordingly, the Court DENIES 7 Plaintiff’s Motion to Remand. 8 A. Operative Complaint 9 To start, the Court conducts its jurisdiction analysis based on the original 10 complaint that was filed in state court, and not the proposed amended complaint. “[P]ost- 11 removal amendments to the pleadings cannot affect whether a case is removable, because 12 the propriety of removal is determined solely on the basis of the pleadings filed in state 13 court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006).
discussed Cited as authority (rule) Lewis v. Chase Airport Management Inc.
S.D. Cal. · 2020 · confidence medium
“Dismissal of the federal claim would . . . ordinarily . . 22 . authorize[] the district court to remand the pendent state law claims.” Williams v. Costco 23 Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006) (citing 28 U.S.C. § 1367 (c)(3)). 24 “Supreme Court and Ninth Circuit precedent teaches us that the district court is in 25 the best position to judge the extent of resources invested in a case and that, therefore, the 26 district court’s discretion ought not be lightly disturbed.” Schneider v. TRW, Inc., 938 F.2d 27 986, 993-94 (9th Cir. 1991). “[I]n the usual case in which …
discussed Cited as authority (rule) Marty Linebarger v. Graphic Packaging International, LLC
C.D. Cal. · 2020 · confidence medium
However, the Ninth Circuit has “long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court.” Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006).
discussed Cited as authority (rule) Nevada Collectors Association v. State of Nevada Department of Business and Industry Financial Institutions Division
D. Nev. · 2020 · confidence medium
Legal Standard 11 Ordinarily, the question of whether a federal district court can exercise jurisdiction and 12 whether it should are one and the same: “where the district court is presented with a case within 13 its original jurisdiction, it has ‘a “virtually unflagging obligation” to exercise the jurisdiction 14 conferred upon [it] by the coordinate branches of government and duly invoked by litigants.’” 15 Williams v. Costco Wholesale Corp., 471 F.3d 975, 977 (9th Cir. 2006) (quoting United States v. 16 Rubenstein, 971 F.2d 288, 293 (9th Cir.1992) (quoting in turn Colo. River Wa…
cited Cited as authority (rule) Oksana Baiul-Farina v. Joseph Lemire
9th Cir. · 2020 · confidence medium
Considering the operative complaint at the time of removal, see Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006), we disagree.
discussed Cited as authority (rule) Sampson v. Subaru of America, Inc.
S.D. Cal. · 2019 · confidence medium
Section 1447(e) provides: 12 If after removal the plaintiff seeks to join additional defendants whose joinder would destroy subject matter jurisdiction, the court may deny joinder, or 13 permit joinder and remand the action to the State court. 14 “[T]he decision regarding joinder of a diversity destroying-defendant is left to the 15 discretion of the district court.” Newcombe v. Adolf Coors Co., 157 F.3d 686, 691 (9th Cir. 16 1998). 17 “Once a case has been properly removed, the district court has jurisdiction over it on 18 all grounds apparent from the complaint, not just those cited in…
cited Cited as authority (rule) The Regents of the Uc v. Paul Aisen
9th Cir. · 2018 · confidence medium
See Rockwell Int’l Corp. v. United States, 549 U.S. 456 , 474 n.6 (2007); Williams v. Costco Wholesale Corp., 471 F.3d 975, 976 (9th Cir. 2006). 4 ownership or right to possession based on state law.
Retrieving the full opinion text from the archive…
Scott M. Williams, an Individual and All Others Similarly Situated
v.
Costco Wholesale Corporation, a Washington Corporation, Dba Costco, and Does 1-150, Inclusive
03-56093.
Court of Appeals for the Ninth Circuit.
Dec 6, 2006.
471 F.3d 975

471 F.3d 975

Scott M. WILLIAMS, an individual and all others similarly situated, Plaintiff-Appellee,
v.
COSTCO WHOLESALE CORPORATION, a Washington corporation, dba Costco, Defendant-Appellant, and
Does 1-150, inclusive, Defendants.

No. 03-56093.

United States Court of Appeals, Ninth Circuit.

Argued and Submitted August 16, 2006.

Filed December 6, 2006.

Kenwood C. Youmans, David D. Kadue & Thomas J. Wybenga, Seyfarth Shaw LLP, Los Angeles, CA, for the appellant.

Frank J. Coughlin, Coughlin & Conforti, Santa Ana, CA; Earl R. Wallace, Ruzicka, Snyder & Wallace, LLP, Newport Beach, CA, for the respondent.

Appeal from the United States District Court for the Southern District of California; Napoleon A. Jones, District Judge, Presiding. D.C. No. CV-02-02003-NAJ/JFS.

Before: KOZINSKI, O'SCANNLAIN and BYBEE, Circuit Judges.

PER CURIAM:

1

Williams sued Costco in California state court, alleging violations of federal and state law. Costco properly removed the case to district court, relying on federal question jurisdiction. After removal, Williams amended his complaint to eliminate the only federal claim and to add new state law claims. He then filed a motion to remand. The district court held that it had discretion to remand the state law claims, and did so.

2

At the time Williams filed his motion to remand, however, the district court had jurisdiction over the remaining state law claims based on diversity of citizenship. The district court recognized this,[1] but held that Costco could not rely on this ground because it had not filed a second removal notice within 30 days of the amended complaint — the document that had first made it clear that the requirements for diversity were satisfied.[2]

3

The district court erred.[3] We have long held that post-removal amendments to the pleadings cannot affect whether a case is removable, because the propriety of removal is determined solely on the basis of the pleadings filed in state court. See Sparta Surgical Corp. v. Nat'l Ass'n of Sec. Dealers, Inc., 159 F.3d 1209, 1213 (9th Cir.1998); O'Halloran v. Univ. of Wash., 856 F.2d 1375, 1379 (9th Cir.1988). It follows that a party that has properly removed a case need not amend its removal notice or file a new notice after an amended complaint changes the ground for federal jurisdiction. Because post-removal pleadings have no bearing on whether the removal was proper, there is nothing a defendant can or need do to perfect the removal. See Yarnevic v. Brink's, Inc., 102 F.3d 753, 755 (4th Cir.1996). Indeed, the idea of filing a notice of removal in a case that is already pending in federal court, having been properly removed, is nonsensical. After all, "a Supplemental Notice of Removal would, if granted, have the effect of removing a case that has already been removed." Nolan v. Boeing Co., 715 F.Supp. 152, 153 n. 1 (E.D.La. 1989).

4

Once a case has been properly removed, the district court has jurisdiction over it on all grounds apparent from the complaint, not just those cited in the removal notice. See Brockman v. Merabank, 40 F.3d 1013, 1016 (9th Cir.1994). Any post-removal pleadings must be treated just as they would be in a case originally filed in federal court. Here, the district court had authority over the state law claims in the original complaint only on the basis of supplemental jurisdiction. See 28 U.S.C. § 1367. Dismissal of the federal claim would thus, ordinarily, have authorized the district court to remand the pendent state law claims. Id. § 1367(c)(3). But, as defendant pointed out below, the amended complaint presented an independent jurisdictional basis for the state law claims, namely diversity. With rare exceptions not applicable here,[4] where the district court is presented with a case within its original jurisdiction, it has "a `virtually unflagging obligation' to exercise the jurisdiction conferred upon[it] by the coordinate branches of government and duly invoked by litigants." United States v. Rubenstein, 971 F.2d 288, 293 (9th Cir. 1992) (quoting Colo. River Water Conservation Dist. v. United States, 424 U.S. 800, 817, 96 S.Ct. 1236, 47 L.Ed.2d 483 (1976)). The district court had no discretion to remand these claims to state court.

5

REVERSED.

Notes:

1

The district court seems to have believed that William's original complaint, the one filed in state court, was unclear as to whether the amount in controversy exceeded $75,000, but the amended complaint cured this uncertainty. We have some doubt that the original complaint failed to clearly allege the jurisdictional amount, but it makes no difference. If the original complaint in fact supported federal jurisdiction on both diversity and federal question grounds, Costco was not required to list both grounds in its notice of removal. The civil removal statute, unlike the removal statute for criminal cases, has no requirement that all grounds for removal be listed in the noticeCompare 28 U.S.C. § 1446(b) with id. § 1446(c)(2). And, if the original complaint already stated a claim for diversity of citizenship, the question that distracted the district court — i.e., whether Costco was required to file a second notice of removal — is rendered moot.

2

The district court derived the 30-day time-limit from the second paragraph of 28 U.S.C. § 1446(b), which deals with the situation where the grounds for removal are not apparent from the original state-court pleading, but become apparent upon the filing of an amended pleading or other paper. In such circumstances a defendant has 30 days from service of this document to file a notice of removal

3

Because this remand was not based on lack of subject matter jurisdiction or any defect in the removal — the grounds for which 28 U.S.C. § 1447(d) bars appellate review — we may review the remand orderSee Quackenbush v. Allstate Ins. Co., 517 U.S. 706, 711-12, 116 S.Ct. 1712, 135 L.Ed.2d 1 (1996).

4

Neither plaintiff nor the district court has suggested that this is the rare case where abstention may be appropriateSee Quackenbush, 517 U.S. at 716-17, 116 S.Ct. 1712.