                   FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

JENNIFER L. LASTER; ANDREW               
THOMPSON; ELIZABETH VOORHIES,
on behalf of themselves and all
others similarly situated and on
behalf of the general public,                 No. 08-56394
                           Plaintiffs,
                                                D.C. No.
                 and
                                            3:05-cv-01167-
VINCENT CONCEPCION; LIZA                       DMS-AJB
CONCEPCION,                                     OPINION
             Plaintiffs-Appellees,
              v.
AT&T MOBILITY LLC,
            Defendant-Appellant.
                                         
        Appeal from the United States District Court
           for the Southern District of California
         Dana M. Sabraw, District Judge, Presiding

                  Argued and Submitted
       September 17, 2009—San Francisco, California

                    Filed October 27, 2009

     Before: Mary M. Schroeder, Stephen Reinhardt and
              Carlos T. Bea, Circuit Judges.

                    Opinion by Judge Bea




                             14387
14390           LASTER v. AT&T MOBILITY LLC


                          COUNSEL

Donald M. Falk, Mayer Brown LLP, Palo Alto, California, for
the defendant-appellant.

Kirk B. Hulett, Hullet Harper Stewart LLP, San Diego, Cali-
fornia, for the plaintiffs-appellees.


                          OPINION

BEA, Circuit Judge:

   This case involves a class action claim that a telephone
company’s offer of a “free” phone to anyone who signs up for
its service is fraudulent to the extent the phone company
charges the new subscriber sales tax on the retail value of
each “free” phone.

   The phone company demanded the plaintiffs’ claims be
submitted to individual arbitration, pointing to the arbitration
clause of the written agreement, which arbitration clause
requires arbitration, but bars class actions. Because this is an
action invoking diversity of citizenship jurisdiction, the
plaintiff-subscribers point to California contract law, which
they claim renders both the arbitration clause and the class
action waiver unconscionable, hence, unenforceable.

   At first blush, it seems we decided the invalidity of an arbi-
tration agreement banning class actions in Shroyer v. New
                   LASTER v. AT&T MOBILITY LLC                       14391
Cingular Wireless Services, Inc., 498 F.3d 976 (9th Cir.
2007). But, the phone company points to a new wrinkle:
unlike the arbitration clause in Shroyer, this arbitration clause
provides for a “premium” payment of $7,500 (the jurisdic-
tional limit of California’s small claims court) if the arbitrator
awards the customer an amount greater than the phone com-
pany’s last written settlement offer made before selection of
an arbitrator. Hence, says the phone company, the arbitration
clause is not an artifice that has the practical effect of render-
ing it immune from individual claims.

   We will find, on second blush, the new “premium” pay-
ment does not distinguish this case from Shroyer, and that
under California law, the present arbitration clause is uncon-
scionable and unenforcable. Further, we will also find no
merit to the phone company’s claim the Federal Arbitration
Act (FAA) preempts California unconscionability law.

     Thus, we will affirm the district court’s order.

I.       Factual and Procedural History

  In February 2002, Vincent and Liza Concepcion signed a
Wireless Service Agreement (WSA) with AT&T Mobility1
(AT&T) for cellular phone service and the purchase of new
cell phones. The Concepcions received the cell phones with-
out charge for the devices themselves because they agreed to
a two-year contract term. However, AT&T charged them
$30.22 total in sales tax for the two phones2, calculated as
     1
     The original contract was with Cingular Wireless. In November of
2005, AT&T acquired Cingular Wireless and renamed the company
AT&T Mobility (AT&T) on January 8, 2007.
   2
     The Concepcions allege they were actually charged $149.99 for a
Motorola phone, and $0.00 for a Nokia phone. If so, at a sales tax rate of
7.75%, the amount of sales tax charged on the “free” Nokia phone is but
$18.60. For purposes of the present appeal, the disparity in their pleadings
is inconsequential. If anything, it makes the predictable recovery in an
individual claim smaller and more likely to have the practical effect of
making the arbitration clause unconscionable.
14392             LASTER v. AT&T MOBILITY LLC
7.75% of both phones’ full retail value. The Concepcions con-
tinued to renew their WSA through the filing of this lawsuit.

   The WSA included both an arbitration clause, which
required any disputes to be submitted to arbitration, and a
class action waiver clause, which required any dispute
between the parties to be brought in an individual capacity. In
December 2006, AT&T revised the arbitration agreement to
add a new premium payment clause. Under this clause,
AT&T will pay a customer $7,5003 if the arbitrator issues an
award in favor of a California customer that is greater than
AT&T’s last written settlement offer made before the arbitra-
tor was selected.

   On March 27, 2006, before the premium payment clause
was added, the Concepcions filed a complaint in the United
States District Court for the Southern District of California.
The Concepcions alleged the practice of charging sales tax on
a cell phone advertised as “free” was fraudulent. In September
2006, the district court consolidated the Concepcions’ case
with the Laster case, a putative class action addressing the
same issues. In March 2008, after the premium payment
clause was added, AT&T filed a motion to compel the Con-
cepcion plaintiffs to submit their claims to individual arbitra-
tion under the revised arbitration agreement. The district court
denied the motion. It held that the class waiver provision of
the arbitration agreement is unconscionable under California
law and that California unconscionability law is not pre-
empted by the Federal Arbitration Act. AT&T timely
appealed.
  3
    The agreement specifically provides for a premium payment in the
amount of “the maximum claim that may be brought in small claims court
in the county of your billing address.” In California, the maximum claim
is $7,500. Cal. Code Civ. Proc. § 116.221.
                LASTER v. AT&T MOBILITY LLC              14393
II.    Jurisdiction and Standard of Review

   This is an interlocutory appeal from the denial of a motion
to compel arbitration. We have jurisdiction under 9 U.S.C.
§ 16(a)(1)(B). We review the denial of a motion to compel
arbitration de novo. Shroyer v. New Cingular Wireless Ser-
vices, Inc., 498 F.3d 976, 981 (9th Cir. 2007).

III.   Discussion

  A.    AT&T’s class action waiver is unconscionable
        under California law.

   [1] The district court did not err when it held AT&T’s class
action waiver was unconscionable under California law, and
thus unenforceable. Under the Federal Arbitration Act, arbi-
tration agreements “shall be valid, irrevocable, and enforce-
able save upon such grounds as exist at law or in equity for
the revocation of any contract.” 9 U.S.C. § 2. “It is well-
established that unconscionability is a generally applicable
contract defense, which may render an arbitration provision
unenforceable.” Shroyer, 498 F.3d at 981 (internal citations
omitted).

   [2] To be unenforceable under California law, a contract
provision must be both procedurally and substantively uncon-
scionable. Id. at 981. Procedural unconscionability generally
takes the form of a contract of adhesion, that is, a contract
drafted by the party of superior bargaining strength and
imposed on the other, without the opportunity to negotiate the
terms. Id at 982. Substantive unconscionability focuses on
overly harsh or one-sided contract terms. Id. Both elements of
unconscionability need not be present to the same degree;
California courts use a sliding-scale: the more substantively
unconscionable the contract term, the less procedurally
unconscionable it need be to be unenforceable and vice versa.
Id. at 981-82.
14394              LASTER v. AT&T MOBILITY LLC
   [3] The California Supreme Court addressed the uncons-
cionability of class action waivers in arbitration agreements
for the first time in Discover Bank v. Sup. Ct., 113 P.3d 1100
(Cal. 2005), holding that class action waivers were at least
sometimes unconscionable under California law. 113 P.3d at
1108. Class actions, the court reasoned, serve the important
policy function of deterring and redressing wrongdoing, par-
ticularly where a company defrauds large numbers of con-
sumers out of individually small sums of money.4 Id. at 1105.
Class action waivers pose a problem because, “small recov-
eries do not provide the incentive for any individual to bring
a solo action prosecuting his or her rights.” Id. at 1106. In this
way, the class action waiver allows the company to insulate
itself from liability for its wrongdoing and the policy behind
class actions is thwarted. Id. at 1109. With this in mind, the
Discover Bank court held:

      when the [class] waiver is found in a consumer con-
      tract of adhesion in a setting in which disputes
      between the contracting parties predictably involve
      small amounts of damages, and when it is alleged
      that the party with the superior bargaining power has
      carried out a scheme to deliberately cheat large num-
      bers of consumers out of individually small sums of
      money, then, at least . . . the waiver becomes in prac-
      tice the exemption of the party from responsibility
      for its own fraud, or willful injury to the person or
      property of another. Under these circumstances, such
      waivers are unconscionable under California law and
      should not be enforced.
  4
   As the California Supreme Court has emphasized, “Some courts have
viewed class actions or arbitrations as a merely procedural right, the
waiver of which is not unconscionable. . . . But as [the cases] of this court
have continually affirmed, class actions and arbitrations are, particularly
in the consumer context, often inextricably linked to the vindication of
substantive rights.” Discover Bank, 113 P.3d at 1109.
                   LASTER v. AT&T MOBILITY LLC              14395
Id. at 1110 (internal quotations omitted). The reasoning
behind this rule is pretty easy to grasp. As we explained in
Shroyer: “when the potential for individual gain is small, very
few plaintiffs, if any, will pursue individual arbitration or liti-
gation, which greatly reduces the aggregate liability a com-
pany faces when it has exacted small sums from millions of
consumers.” 498 F.3d at 986.

   [4] We have interpreted Discover Bank as creating a three-
part test to determine whether a class action waiver in a con-
sumer contract is unconscionable: (1) is the agreement a con-
tract of adhesion; (2) are disputes between the contracting
parties likely to involve small amounts of damages; and (3) is
it alleged that the party with superior bargaining power has
carried out a scheme deliberately to cheat large numbers of
consumers out of individually small sums of money. Id. at
983. In Shroyer, we noted that “there are most certainly cir-
cumstances in which a class action waiver is unconscionable
under California law despite the fact that all three parts of the
Discover Bank test are not satisfied.” Id. Because we hold that
the class action waiver at issue satisfies all three parts of the
test, as was true in Shroyer, “it is unnecessary to explore those
circumstances here.” Id.

    1.        AT&T’s class action waiver is unconscionable
              under the three-part Discover Bank test.

         a.    AT&T’s WSA is a contract of adhesion.

   [5] As we noted in Shroyer, a contract of adhesion under
California law is a standardized contract imposed on the sub-
scribing party without an opportunity to negotiate the terms.
Id. The Concepcions were given the standardized WSA with-
out the opportunity to negotiate the terms. Thus, under Cali-
fornia law, it is a contract of adhesion.
14396            LASTER v. AT&T MOBILITY LLC
        b.   The dispute involves predictably small amounts
             of damages.

   [6] In both Shroyer and Discover Bank the damages at issue
were found to be “predictably small.” The plaintiffs in
Shroyer sued under cell phone contracts, claiming damages in
the “hundreds of dollars” range based on the cost of obtaining
new cell phone service with other companies. 498 F.3d at
984. In Discover Bank, the plaintiff sought to recover a $29
fee charged for late credit card payments that were claimed
not to be late. 113 P.3d at 1104. Each court determined that
these amounts were small enough to satisfy the second prong
of the Discover Bank test. See Shroyer, 498 F.3d at 984; Dis-
cover Bank, 113 P.3d at 1110. Here, the damages are $30.225
for the sales tax charged on cell phones AT&T advertised
were “free.” This is comparable to the amount of damages in
Discover Bank, and well below the hundreds of dollars found
predictably small in Shroyer.

        c.   The Concepcions alleged AT&T carried out a
             scheme deliberately to cheat large numbers of
             consumers out of small sums of money.

  [7] The Concepcions alleged in their complaint that AT&T
was fraudulently advertising the phones were free, all the
while knowing AT&T would charge consumers sales tax on
such phones. This is sufficient to satisfy the third-prong of
Discover Bank. See id. at 984.

        d.   Conclusion

  [8] Because all three prongs of the Discover Bank test are
met, AT&T’s class action waiver is unconscionable under
California law.
  5
   Or $18.60, see supra note 2.
                  LASTER v. AT&T MOBILITY LLC                      14397
      2.   AT&T’s premium payment provision does not
           negate the unconscionability of the class action
           waiver under California law.

   [9] AT&T contends the premium payment provision of its
revised arbitration agreement6 prevents the class action waiver
from being substantively unconscionable. AT&T reasons that
the potential for the premium payment overcomes the prob-
lem of predictably small damages identified in Discover Bank
and Shroyer. AT&T submits an award of $7,500 should pro-
vide individual customers an adequate incentive to pursue ini-
tially small damage claims with higher potential, against the
company. AT&T contends that this incentive-laden scheme
actually punishes it should it make low-ball offers in settle-
ment, and it removes any claim of immunity from lability for
its allegedly fraudulent conduct; therefore this class waiver is
not unconscionable. However, this is incorrect. The Discover
Bank rule focuses on whether damages are predictably small,
and in the end, the premium payment provision does not
transform a $30.22 case into a predictable $7,500 case.

   [10] The $7,500 premium payment is available only if
AT&T does not make a settlement offer to the aggrieved cus-
tomer in a sum equal to or higher than is ultimately awarded
in arbitration, and before an arbitrator is selected. This means
that if a customer files for arbitration7 against AT&T, predict-
  6
     The provision provides for a contractual payment of $7,500 if a cus-
tomer receives an arbitration award greater than the amount of AT&T’s
last written settlement offer, made before an arbitrator was chosen.
   7
     AT&T puts much stock in the argument that, while a customer might
not be bothered to arbitrate or litigate small damage claims, a customer
would be willing to pursue a small damage claim through AT&T’s infor-
mal claims process. However, were this the case it would not affect the
outcome. We must determine only whether the premium provides ade-
quate incentive to pursue individual arbitration, not informal resolution.
See Discover Bank, 113 P.3d at 1110 (“[n]or do we agree . . . that small
claims litigation, government prosecution, or informal resolution are ade-
quate substitutes [for the class action mechanism].”) (emphasis added).
14398              LASTER v. AT&T MOBILITY LLC
ably, AT&T will simply pay the face value of the claim
before the selection of an arbitrator to avoid potentially pay-
ing $7,500. Thus, the maximum gain to a customer for the
hassle of arbitrating a $30.22 dispute is still just $30.22.8 We
held in Shroyer that a claim worth a few hundred dollars did
not provide adequate incentive for a customer to bother pursu-
ing individual arbitration. 498 F.3d at 986. The $30.22 at
issue here is even less of an incentive to file a claim. As a
result, aggrieved customers will predictably not file claims—
even if the odds are that after the letter-writing and arbitrator-
choosing, they will get a $30.22 offer—thereby “greatly
reduc[ing] the aggregate liability” AT&T faces for allegedly
mulcting small sums of money from many consumers. See id.
The premium payment provision has no effect on this conclu-
sion,9 nor do any of the other provisions of AT&T’s revised
arbitration clause.10 The actual damages a customer will
recover remain predictably small, thus under the rationale of
  8
     The problem with small damage claims is not that the monetary cost
of arbitrating is greater than the potential recovery, but that a person nor-
mally will not find it worth the time or the hassle to try to recover such
a small amount, even if that person spends no money to hire an attorney
or to invoke the arbitration process. See Shroyer, 498 F.3d at 986.
   9
     The provision does essentially guarantee that the company will make
any aggrieved customer whole who files a claim. Although this is, in and
of itself, a good thing, the problem with it under California law—as we
read that law—is that not every aggrieved customer will file a claim.
   10
      In addition to the $7,500 premium payment, the revised arbitration
agreement also provides: double attorney’s fees in the event the arbitrator
awards the customer more than AT&T’s last written settlement offer
before the arbitrator was selected; AT&T will pay all arbitration costs and
fees unless the arbitrator determines that the claim was frivolous or
brought for an improper purpose; AT&T will not seek attorney’s fees if
it prevails; either party may bring a claim in small claims court; the arbi-
tration is not confidential; full court remedies, including punitive damages
and injunctions, are available; arbitration will be conducted pursuant to
AAA’s Commercial Dispute Resolution Procedures and the Supplemen-
tary Procedures for Consumer-Related Disputes, the arbitration will take
place in the county of the customer’s billing address, and that the customer
can choose between an in-person, telephonic, or no hearing at all for
claims of less than $10,000.
                 LASTER v. AT&T MOBILITY LLC               14399
Discover Bank and Shroyer, AT&T’s class action waiver is in
effect an exculpatory clause, hence substantively unconscio-
nable.

  B.     The Federal Arbitration Act does not preempt Cali-
         fornia unconscionability law.

   The Federal Arbitration Act does not expressly or impliedly
preempt California law governing the unconscionability of
class action waivers in consumer contracts of adhesion. The
FAA “does not bar federal or state courts from applying gen-
erally applicable state contract law principles and refusing to
enforce an unconscionable class action waiver in an arbitra-
tion clause.” Shroyer, 498 F.3d at 987. Shroyer controls this
case because AT&T makes the same arguments we rejected
there.

    1.    The FAA does not expressly preempt California
          law.

   [11] The FAA provides that arbitration clauses “shall be
valid, irrevocable, and enforceable, save upon such grounds
as exist at law or in equity for the revocation of any contract.”
9 U.S.C. § 2. Therefore, if a state-law ground to revoke an
arbitration clause is not also applicable as a defense to revoke
a contract in general, that state-law principle is preempted by
the FAA. Shroyer, 498 F.3d at 987. However, “because
unconscionability is a generally applicable contract defense,
it may be applied to invalidate an arbitration agreement with-
out contravening § 2 of the FAA” Id. at 988 (internal quota-
tions omitted).

   AT&T contends the Discover Bank rule abandons the
sliding-scale approach of California general unconscionability
law and is therefore a “new rule” applicable only to arbitra-
tion agreements. This contention is incorrect. As we explained
in Shroyer, “[t]he rule announced in Discover Bank is simply
a refinement of the unconscionability analysis applicable to
14400           LASTER v. AT&T MOBILITY LLC
contracts generally in California.” 498 F.3d at 987. Essen-
tially, the Discover Bank test applies the general sliding-scale
approach to unconscionability in the specific context of class
action waivers. The best way to read Discover Bank in light
of the sliding-scale approach is that, if a contract clause is, in
practice, exculpatory, as long as there is any degree of proce-
dural unconscionability, the element of substantive uncons-
cionability is generally adequate, as a matter of law. See
Discover Bank, 113 P.3d at 1109 (holding that exculpatory
clauses are substantively unconscionable, and when contained
in procedurally unconscionable adhesive contracts, “generally
unconscionable”).

   [12] Moreover, in Shroyer, we already rejected the argu-
ment that Discover Bank subjects “arbitration clauses to spe-
cial scrutiny.” Id. at 987. AT&T is making the same
preemption arguments already rejected in Shroyer. As a panel,
we are bound by a prior panel’s determination of law. Gen-
eral Const. Co. v. Castro, 401 F.3d 963, 975 (9th Cir. 2005).
Shroyer controls, therefore California law is not expressly
preempted by the FAA.

    2.   The FAA does not impliedly preempt California
         law.

   [13] Neither does the FAA impliedly preempt California
unconscionability law. A state law is impliedly preempted
where it “stands as an obstacle to the accomplishment and
execution of the full purposes and objectives of Congress.”
Shroyer, 498 F.3d at 988. Determining whether California’s
unconscionability principles stand as an obstacle to the FAA
first requires identification of the purposes and objectives
underlying the federal Act. Id. at 988-89. In Shroyer, we iden-
tified two purposes: first, to reverse judicial hostility to arbi-
tration agreements by placing them on the same footing as
any other contract, and second, to promote the efficient and
expeditious resolution of claims. Id. at 989.
                LASTER v. AT&T MOBILITY LLC                14401
   [14] In Shroyer, we held that California unconscionability
law did not stand in the way of either of these identified pur-
poses. Id. at 989-91. As to “reversing hostility to arbitration
and placing arbitration agreements on the same footing as
ordinary contracts,” this is not “frustrated or undermined in
any way by a holding that class arbitration waivers in con-
tracts of adhesion, like class action waivers in such contracts
are unconscionable.” Id. at 990. Rather, “Discover Bank
placed arbitration agreements with class action waivers on the
exact same footing as contracts that bar class action litigation
outside the context of arbitration.” Id. We further explained,
“the fact that § 2 expressly permits a court to decline enforce-
ment of an arbitration agreement on grounds . . . such as
unconscionability, strongly suggests that Congress did not
contemplate that implied preemption principles would be
applied to mandate the opposite result.” Id. at 989-90.

   As to the second purpose identified, we rejected the “con-
tention that class proceedings will reduce the efficiency and
expeditiousness of arbitration in general.” Id. at 990. For these
reasons, we held that “applying California’s generally appli-
cable contract law to refuse enforcement of the unconsciona-
ble class action waiver in this case does not stand as an
obstacle to the purposes or objectives of the Federal Arbitra-
tion Act, and is, therefore, not impliedly preempted.” Id. at
993.

   Here, AT&T makes the same arguments regarding conflict
preemption that we rejected in Shroyer. Compare Opening Br.
at 51-53 (arguing that class proceedings would hinder a
speedy resolution, place extra burdens on the arbitral process,
and lead to companies abandoning arbitration altogether) with
Shroyer, 498 F.3d at 989 (noting that appellant argued class
proceedings would hinder the “speed, simplicity, cost savings,
informality, and reduced adversariality” of arbitration and
lead to companies abandoning arbitration). AT&T even
admits the court in Shroyer “rejected a similar argument.”
Opening Br. at 49. However, AT&T attempts to distinguish
14402            LASTER v. AT&T MOBILITY LLC
this case from Shroyer by contending that a recent Supreme
Court case, Preston v. Ferrer, 128 S. Ct. 978 (2008), super-
cedes Shroyer’s reasoning on this point.

   Preston, an attorney, performed services for Ferrer regard-
ing Ferrer’s role as “Judge Alex” on a Fox television network
program. 128 S. Ct. at 982. Preston filed an arbitration
demand seeking fees allegedly owed him by Ferrer under
their contract. Id. Ferrer responded by petitioning the Califor-
nia Labor Commissioner to declare the entire contract invalid
under the California Talent Agencies Act (TAA). Id. Ferrer
contended that Preston was acting as a talent agent without
the license required by the TAA, thus rendering their entire
contract void. Id.

   [15] Preston responded by filing a motion to compel arbi-
tration. Id. The trial court denied the motion to compel arbi-
tration, and the denial was affirmed on appeal, on the ground
the TAA vested primary exclusive jurisdiction in the Califor-
nia Labor Commissioner to determine who was or was not a
talent agent. Id. The U.S. Supreme Court granted certiorari
and reversed, noting that Buckeye Check Cashing, Inc. v. Car-
degna, 546 U.S. 440 (2006) “largely, if not entirely, resolves
the dispute before us.” Id. at 984. According to the Court in
Preston, Buckeye held that when parties agree to arbitrate all
disputes arising under their contract, questions concerning the
validity of the entire contract are to be resolved by the arbitra-
tor in the first instance, not a federal or state court. Id. at 981.
Thus, in Preston, the Supreme Court held that because Fer-
rer’s allegation that Preston was acting as an unlicensed talent
agent was a challenge to the validity of the contract as a
whole, as opposed to the validity of the arbitration clause
itself, the TAA’s attempt to lodge primary jurisdiction in
another forum was superceded by the FAA. Id. at 984, 987.
The Court expressly recognized, however, that attacks on the
validity of the entire contract are distinct from attacks aimed
solely at the arbitration clause. Id. at 984. Thus, by its terms,
Preston is inapplicable to our case because the Concepcions
                LASTER v. AT&T MOBILITY LLC              14403
are not challenging the validity of the service contract with
AT&T as a whole, but only the validity of the arbitration
agreement. Likewise, nothing in Preston undercuts the ratio-
nale of Shroyer that the FAA does not impliedly preempt Cal-
ifornia unconscionability law, because the plaintiffs in
Shroyer were also challenging only the validity of the arbitra-
tion agreement. Because Shroyer still controls, California
unconscionability law is not impliedly preempted by the
FAA.

IV.   Conclusion

  We affirm the district court’s denial of AT&T’s motion to
compel arbitration.

  AFFIRMED.
