Per Curiam Opinion; Concurrence by Judge O’SCANNLAIN; Concurrence by Judge GRABER.
PER CURIAM:
We must decide whether a putative class can be certified in this securities ■ fraud class action.
I
This appeal stages the last act of a long drama that followed the collapse of an elaborate stock manipulation scheme.
A
Genesislntermedia, Inc. (“GENI”) is a Delaware corporation with its registered address in California. Its stock once traded on the NASDAQ, but since late 2001 has traded over the counter but off the NASDAQ.1 Turmoil in GENI’s stock price began in the fall of 2001 and continued as the details emerged of what the plaintiffs allege was a sophisticated scheme to manipulate the price of the company’s stock.
Appellants — Amish Desai, Christopher and Therese Long, and Elizabeth Lamb (“Investors”)- — allege that Deutsche Bank Securities Ltd. (“DBSL”), Deutsche Bank Securities, Inc., and Deutsche Bank AG (collectively, “Deutsche Bank”), through Wayne Breedon, a vice-president at DBSL, masterminded this stock price manipulation scheme.2 Breedon and [934]*934Deutsche Bank, however, played only one part in the plot that Investors allege. Some background, therefore, is necessary.
A common way to manipulate the market in a security is to cause its price to increase by creating the illusion of more investor interest than really exists. The manipulator acquires shares of the security before the price increase, then slowly sells them off and reaps the profit. The problem with this model, however, is that as the manipulator sells off his shares he depresses the price, which lessens his profit. Investors here allege a scheme that varied the theme in a way designed to cure this problem. It involved a commercial arrangement known as a securities loan.
In the typical securities loan, a broker-dealer lends securities to another broker-dealer, the loan being secured by cash collateral the borrower gives to the lender. See generally Stephenson v. Deutsche Bank AG, 282 F.Supp.2d 1032, 1044-45 (D.Minn.2003). The borrower of the security receives so-called rebate payments, which are like interest on the cash collateral he has transferred to the security lender.3 As the value of the security increases, the amount of cash collateral and the level of interest also increase. Adjustments— marking the securities to the market — -are made daily.
According to Investors, a web of schemers (including several persons no longer defendants) used securities loans to profit contemporaneously with the inflation of GENI’s stock price, rather than by selling the stock after the price rose (which would have depressed the price). It worked as follows.4
Officers of GENI first issued themselves unregistered shares of the company. Such shares may not be publicly traded, but the GENI officers loaned them to a broker-dealer called Native Nations Securities, Inc., receiving cash collateral in return. Richard Evangelista, an employee of Native Nations and apparently a longtime associate of Breedon, falsified the records of his employer to make it look like the GENI shares had come from other broker-dealers. Native Nations then lent the shares (cash collateral coming back) to Deutsche Bank. Breedon was in charge of this account, which continued to absorb unregistered shares of GENI stock. Eventually, Breedon and his associates at GENI developed a chain of broker-dealers that came between Native Nations and Deutsche Bank in order to increase the amount of capital for the scheme and to insulate Deutsche Bank from any fallout should the scheme collapse.
The GENI officers used the cash collateral to day-trade in GENI’s publicly traded shares. This created the appearance of investor demand. That appearance inflated the stock price, which in turn required the borrowers of GENI stock, from Native Nations to Deutsche Bank, to provide [935]*935more cash collateral to feed the cycle. It also increased the rebate payments to the borrowers, from Native Nations down the line to Deutsche Bank. It seems Deutsche Bank gained the most from the rebate payments, however, because the intermediary broker-dealers in the chain paid out a percentage of the rebates they received to the next party in the chain. Deutsche Bank, being the last in line, did not have to do that.
To ensure that GENI’s price kept climbing, Breedon and his associates at GENI allegedly paid off two stock analysts to recommend GENI stock in order to drum up demand. One of the analysts was Courtney Smith, a one-time defendant in this litigation; the Longs claim that they purchased GENI stock in February of 2000 on the basis of Smith’s bogus recommendations. The secret deal between GENI and Smith later came to light in the news media.
As the district court put it, this scheme solved the classic problem of market manipulators everywhere: it allowed them to profit from fraudulently inflating a stock’s price without having to sell the shares.
By September 11, 2001, the scheme had driven GENI’s stock price from $12 per share to over $52 per share. The terrorist attacks that day stopped all trading in the markets until September 17. When trading resumed, the share price fell dramatically for reasons that are unclear. By September 25, GENI stock was down to $9 per share, at which point trading in the stock was suspended. GENI delisted its stock from NASDAQ soon after; it now trades for pennies.
As the price collapsed in September of 2001, borrowers of the stock, starting with Deutsche Bank, demanded their cash collateral back. The cash calls went up the chain to Native Nations. Though Deutsche Bank was able to recover nearly all the collateral it had pledged, the intermediary broker-dealers were not so lucky. GENI had spent the cash collateral, so it could not return it to Native Nations, which left the broker-dealer, and many of the other broker-dealers between it and Deutsche Bank, insolvent. Thus, Deutsche Bank had profited through the rebate payments it received, but it had managed to recover almost of all the cash collateral it had advanced.
B
Investors seek to represent a class of people who bought GENI stock in the putative class period, which is December 21,1999, to September 25, 2001. They sue under §§ 10(b) and 20(a) of the Securities Exchange Act of 1934 (“the 1934 Act”), codified at 15 U.S.C. §§ 78j(b) and 78t(a), respectively. Desai, the lead plaintiff, purchased 50,000 shares on the last day of the period. Lamb bought 100 shares on September 20, 2001. The Longs, as mentioned, bought their 100 shares in February of 2000 after seeing analyst Courtney Smith’s recommendations on television.
This case began over seven years ago, but it remains at the class certification stage. In October of 2001, several parties, Desai apparently among them, filed putative class actions in United States District Court for the Central District of California, Judge Stephen V. Wilson presiding. Originally, they alleged that GENI, its officers, and their associates had made misrepresentations to the public or paid others to do so to inflate the price of GENI stock. Deutsche Bank was not named a defendant.
After some preliminary wrangling over who would be the lead plaintiff, the California district court appointed Horizon In[936]*936ternational, LLC, an institutional investor, and Desai as lead plaintiffs. When the Third Amended Complaint, on which the two district court opinions relevant to this appeal are based, was filed, Desai and Horizon were the only representative plaintiffs.
In June of 2003, the California district court transferred the case to the United States District Court for the District of Minnesota, where related proceedings were pending in the bankruptcy of MJK Clearing Inc., one of the unfortunate broker-dealers in the chain between Deutsche Bank and GENI. See In re GenesisIntermedia, Inc. Sec. Litig., 232 F.R.D. 321 (D.Minn.2005). Investors’ counsel added Lamb and the Longs as class representatives, and Horizon withdrew as lead plaintiff. Then Investors moved for certification of the class pursuant to Federal Rule of Civil Procedure 23(b)(3). In December of 2005, the Minnesota district court denied the motion. The Eighth Circuit denied Investors’ petition for interlocutory appeal, and the Minnesota district court transferred the case back to Judge Wilson in California.
In March of 2006, the case was reopened in the Central District of California. A little more than two months later, the district court allowed Investors to renew their motion for class certification. Judge Wilson ultimately denied the motion one day after Investors filed a Fourth Amended Complaint. The district court’s order denying the motion therefore assumes that the Third Amended Complaint is the operative complaint, although it was aware that the Longs and Lamb had been added as representative plaintiffs.5 After that, default judgment was entered against some of the defendants, including Breedon, and the claims against the other defendants, except for Deutsche Bank, were dismissed. The last defendant standing, and the only one before us, is Deutsche Bank.
The class representatives then negotiated, as individuals, a settlement with Deutsche Bank, but explicitly preserved their rights to appeal the denial of class certification. The district court entered final judgment and Investors timely appeal.
II
Federal Rule of Civil Procedure 23 governs when a district court may certify a class. All classes must meet the four prerequisites of Rule 23(a) and fall into one of the three categories of class actions defined in Rule 23(b). The Minnesota district court addressed the Rule 23(a) prerequisites, but the California district court ruled only on Rule 23(b) grounds. Some of our sister circuits have concluded that the interlocutory orders of out-of-circuit district courts that transfer a case to an in-circuit district court are reviewable on appeal of the transferee court’s judgment. See, e.g., Chaiken v. VV Publ’g Corp., 119 F.3d 1018, 1025 n. 2 (2d Cir.1997) (“We have jurisdiction to review the interlocutory judgment of the United States Dis[937]*937trict Court for the District of Massachusetts entered prior to the transfer of the case to a district court within our jurisdiction and the issuance by that court of a final order.”). We need not decide whether to endorse such position, however, as we can decide this case on Rule 23(b) alone.
Specifically, Investors seek certification under Rule 23(b)(3). To certify under that provision, the district court must find, first, “that the questions of law or fact common to the members of the class predominate over any questions affecting only individual members,” and, second, “that a class action is superior to other available methods for the fair and efficient adjudication of the controversy.” Fed.R.Civ.P. 23(b)(3) (2005).6 The rule also lists the following “matters pertinent” to the certification decision:
(A) the interests of members of the class in individually controlling the prosecution or defense of separate actions; (B) the extent and nature of any litigation concerning the controversy already commenced by or against members of the class; (C) the desirability or undesirability of concentrating the litigation of the claims in the particular forum; (D) the difficulties likely to be encountered in the management of a class action.
Id.
The California district court concluded that individual questions of law or fact predominated over common ones, which sufficed to take the putative class outside of Rule 23(b)(3). The district court focused on the element of reliance,7 which is required to prove a violation of § 10(b) of the 1934 Act. The district court’s denial of class certification depended on its belief that Investors would have to prove reliance on an individual basis because they could not prove it class-wide.8 See Basic Inc. v. Levinson, 485 U.S. 224, 242, 108 S.Ct. 978, 99 L.Ed.2d 194 (1988) (recognizing that such individualized proof of reliance effectively makes it impossible to proceed as a class, because “individual issues then would ... overwhelm! ] the common ones”).
A ruling on class certification “is subject to a very limited review and will be reversed only upon a strong showing that the district court’s decision was a clear abuse of discretion.” In re Mego Fin. Corp. Sec. Litig., 213 F.3d 454, 461 (9th Cir.2000) (internal quotation marks omitted). The inquiry turns on whether the district court faithfully applied the requirements of Rule 23(b)(3). See, e.g., Armstrong v. Davis, 275 F.3d 849, 867-68 (9th Cir.2001). To review the district court’s decision, we must understand the underlying causes of action.
Investors bring two claims against Deutsche Bank. First, they allege a violation of § 10(b) of the 1934 Act and Rule 10b-5, promulgated thereunder.9 They [938]*938also allege a violation of § 20(a). Section 20(a) extends liability for violations of other provisions of the 1934 Act, including § 10(b), to certain so-called “controlling persons.” Thus, in this case liability under § 20(a) turns on a violation of § 10(b). The district court evaluated the questions of law or fact with respect to the underlying liability for a violation of § 10(b), not with respect to § 20(a). We therefore put § 20(a) aside.
Section 10(b) makes it “unlawful for any person, directly or indirectly ... (b) [t]o use or employ, in connection with the purchase or sale of any security registered on a national securities exchange or any security not so registered ... any manipulative or deceptive device or contrivance in contravention of [the SEC’s rules and regulations].” 15 U.S.C. § 78j. Rule 10b-5 categorizes violations of the statute into three categories:
(a) [t]o employ any device, scheme, or artifice to defraud[;]
(b) [t]o make any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements made, in the light of the circumstances under which they were made, not misleading!;] or
(c) [t]o engage in any act, practice, or course of business which operates or would operate as a fraud or deceit upon any person, in connection with the purchase or sale of any security.
17 C.F.R. § 240.10b-5.
The words are capacious, to be sure, and “[w]hen we deal with private actions under Rule 10b-5, we deal with a judicial oak which has grown from little more than a legislative acorn.” Blue Chip Stamps v. Manor Drug Stores, 421 U.S. 723, 737, 95 S.Ct. 1917, 44 L.Ed.2d 539 (1975). All the same, “Rule 10b-5 encompasses only conduct already prohibited by § 10(b).” Stoneridge Inv. Partners, LLC v. Scientific-Atlanta, Inc., 552 U.S. 148, 128 S.Ct. 761, 768, 169 L.Ed.2d 627 (2008). Thus, the cause of action must be based either on a “manipulative” device or contrivance or on a “deceptive” one. See 15 U.S.C. § 78j(b); ATSI Commc’ns, Inc. v. Shaar Fund, Ltd., 493 F.3d 87, 99 (2d Cir.2007).
Courts have generally categorized deceptive and manipulative devices into misrepresentations, omissions by those with a duty to disclose, or manipulative acts. See, e.g., Ganino v. Citizens Utils. Co., 228 F.3d 154, 161 (2d Cir.2000) (“Section 10(b) of the Exchange Act bars conduct involving manipulation or deception, manipulation being practices that are intended to mislead investors by artificially affecting market activity, and deception being misrepresentation, or nondisclosure intended to deceive.” (internal quotation marks and alteration omitted)); see also Stoneridge, 128 S.Ct. at 769; Cent. Bank of Denver v. First Interstate Bank of Denver, N.A., 511 U.S. 164, 177, 114 S.Ct. 1439, 128 L.Ed.2d 119 (1994). Misrepresentations and most omissions fall under the prohibition of Rule 10b — 5(b), whereas manipulative conduct typically constitutes “a scheme ... to defraud” in violation of Rule 10b-5(a) or a “course of business which operates ... as a fraud or deceit upon any person” in violation of Rule 10b-5(c). See, e.g., In re Initial Pub. Offering Sec. Litig., 241 F.Supp.2d 281, 335 (S.D.N.Y.2003) (treating manipulation as a violation of Rule 10b-5(a) or (c) and misrepresentations and omissions as violations of Rule 10b — 5(b)).
Here, Investors allege manipulative conduct and omissions by Deutsche Bank.10 “Manipulation,” the Supreme [939]*939Court has recognized, “is virtually a term of art when used in connection with securities markets. The term refers generally to practices, such as wash sales, matched orders, or rigged prices, that are intended to mislead investors by artificially affecting market activity.” Santa Fe Indus., Inc. v. Green, 430 U.S. 462, 476, 97 S.Ct. 1292, 51 L.Ed.2d 480 (1977) (internal quotation marks and citation omitted). As for omissions, the term generally refers to the failure to disclose material information about a company, as opposed to affirmative manipulation. See Basic, 485 U.S. at 230, 108 S.Ct. 978. The person who omitted the material information must have had a duty to disclose it to the person supposedly harmed by the omission. See Paracor Fin., Inc. v. Gen. Elec. Capital Corp., 96 F.3d 1151, 1157 (9th Cir.1996) (“Rule 10b-5 is violated by nondisclosure only when there is a duty to disclose.” (internal quotation marks omitted)). Such a duty may arise “from a relationship of trust and confidence between parties to a transaction.” Chiarella v. United States, 445 U.S. 222, 230, 100 S.Ct. 1108, 63 L.Ed.2d 348 (1980).
Regardless of whether a § 10(b) plaintiff alleges a misrepresentation, omission, or manipulation, he must plead and prove the following elements:
(1) ... use or employ[ment of] any manipulative or deceptive device or contrivance; (2) scienter, i.e. wrongful state of mind; (3) a connection with the purchase or sale of a security; (4) reliance, often referred to ... as “transaction causation;” (5) economic loss; and (6) loss causation, ie. a causal connection between the manipulative or deceptive device or contrivance and the loss.
Simpson v. AOL Time Warner Inc., 452 F.3d 1040, 1047 (9th Cir.2006), vacated on other grounds by Avis Budget Group, Inc. v. Cal. State Teachers’ Ret. Sys., — U.S. -, 128 S.Ct. 1119, 169 L.Ed.2d 945 (2008).
Reliance establishes the causal connection between the alleged fraud and the securities transaction. See Stoneridge, 128 S.Ct. at 769 (citing Basic, 485 U.S. at 243, 108 S.Ct. 978). To say that a plaintiff relied on a defendant’s bad act is to say that the defendant’s actions “played a substantial part in the plaintiffs investment decision.” Rowe v. Maremont Corp., 850 F.2d 1226, 1233 (7th Cir.1988). It is thus “often referred to in cases involving the public securities markets ... as ‘transaction causation,’ ” Dura Pharms., Inc. v. Broudo, 544 U.S. 336, 341, 125 S.Ct. 1627, 161 L.Ed.2d 577 (2005), presumably because reliance requires an investor-plaintiff to show that he would not have engaged in the transaction in question had he known about the fraud.
Reliance can be presumed in two situations. In omission cases, courts can presume reliance when the information withheld is material pursuant to Affiliated Ute Citizens v. United States, 406 U.S. 128, 153-54, 92 S.Ct. 1456, 31 L.Ed.2d 741 (1972). Reliance can also be presumed in certain circumstances under the so-called “fraud on the market theory.” Basic, 485 U.S. at 241-49, 108 S.Ct. 978. Precisely to which cases this presumption applies — that is, to misrepresentation, to omission, to manipulation cases, or to some combination of the three — is an issue the parties contest on appeal. The two presumptions are conceptually distinct.
The fraud on the market theory bears some additional explanation. It is a way to show “the requisite causal connection between a defendant’s [bad act] and a plaintiffs injury,” id. at 243, 108 S.Ct. 978, that lies at the heart of the element of reliance. The theory allows plaintiffs to rely on a “rebuttable presumption of investor reliance based on the theo[940]*940ry that investors presumably rely on the market price, which typically reflects the misrepresentation or omission.” No. 84 Employer-Teamster Joint Council Pension Trust Fund v. Am. W. Holding Corp., 320 F.3d 920, 934 n. 12 (9th Cir.2003). The presumption is “based on the hypothesis that, in an open and developed securities market, the price of a company’s stock is determined by the available material information regarding the company and its business.” Basic, 485 U.S. at 241, 108 S.Ct. 978 (internal quotation marks omitted). Therefore, the presumption is usually available “only when a plaintiff alleges that a defendant made material representations or omissions concerning a security that is actively traded in an ‘efficient market.’ ” Binder v. Gillespie, 184 F.3d 1059, 1064 (9th Cir.1999). In other words, the theory allows the plaintiff .to connect causally the defendant’s bad act with the plaintiffs decision to buy or sell the security, by presuming that the plaintiff based his decision on the price of the security and that such price reflects the defendant’s bad act.
Ill
The district court concluded that neither the Affiliated Ute presumption of reliance nor the fraud on the market presumption of reliance applied in this ease. The Affiliated Ute presumption did not apply, according to the court, because this was not primarily an omissions case. The district court rejected the application of the fraud on the market presumption because, by their own admission, Investors could not show an efficient market. Finally, the court rejected their invitation to create a novel presumption of reliance on “the integrity of the market” in the context of manipulation cases. Whether or not they can rely on a presumption of reliance determines whether their putative class can meet the requirements of Rule 23(b)(3). For without a class-wide presumption, Investors would have to prove reliance as to each class member individually.
The presumption of reliance under Affiliated Ute is limited to cases that “can be characterized as ... primarily alleging] omissions.” Id. at 1064. Therefore, if Investors’ putative class action is not such a case, they cannot avail themselves of the Affiliated Ute presumption.
Investors allege that this is an omissions case because “the case as a whole is ... overwhelmingly non-statement based — in other words, omission-based.” In other words, they seem to assume that as long as liability is not based on misrepresentations, then it must be based on omissions. Relatedly, they argue that because Deutsche Bank and the other former defendants “failed to disclose their active manipulation of GENI stock,” they have made an actionable omission. This approach would collapse manipulative conduct claims and omission claims.
We must recognize, however, that manipulative conduct has always been distinct from actionable omissions.
Omissions are generally actionable under Rule 10b — 5(b). As we explained above, they stem from the failure to disclose accurate information relating to the value of a security where one has a duty to disclose it. Paracor Fin., 96 F.3d at 1157. Insider trading cases are a notorious example: the insider who knows nonpublic information and trades on the basis of it has committed an actionable omission. See, e.g., United States v. O’Hagan, 521 U.S. 642, 651-52, 117 S.Ct. 2199, 138 L.Ed.2d 724 (1997); Chiarella, 445 U.S. at 226-30,100 S.Ct. 1108.
Manipulative conduct, by contrast, is actionable under Rule 10b-5(a) or (c) and includes activities designed to affect [941]*941the price of a security artificially by simulating market activity that does not reflect genuine investor demand. See Santa Fe, 430 U.S. at 476-77, 97 S.Ct. 1292; Ernst & Ernst v. Hochfelder, 425 U.S. 185, 199, 96 S.Ct. 1375, 47 L.Ed.2d 668 (1976) (“[Manipulation] connotes intentional or willful conduct designed to deceive or defraud investors by controlling or artificially affecting the price of securities.”). In order to succeed, manipulative schemes must usually remain undisclosed to the general public. See Santa Fe, 430 U.S. at 477, 97 S.Ct. 1292. If such nondisclosure of a defendant’s fraud was an actionable omission, then every manipulative conduct case would become an omissions case. If that were so, then all of the Supreme Court’s discussion of what constitutes manipulative activity would be redundant. We decline to read the Supreme Court’s case law on manipulative conduct as little more than an entertaining, but completely superfluous, intellectual exercise. See Stoneridge, 128 S.Ct. at 769 (listing the three types of § 10(b) actions); Cent. Bank, 511 U.S. at 177,114 S.Ct. 1439 (same).
One of our sister circuits has recently come to a similar conclusion. In Joseph v. Wiles, 223 F.3d 1155 (10th Cir.2000), the Tenth Circuit held the Affiliated Ute presumption inapplicable in a ease involving some omissions, but also misrepresentations and secret manipulation.
Any fraudulent scheme requires some degree of concealment, both of the truth and of the scheme itself. We cannot allow the mere fact of this concealment to transform the alleged malfeasance into an omission rather than an affirmative act. To do otherwise would permit the Affiliated Ute presumption to swallow the reliance requirement almost completely. Moreover, it would fail to serve the Affiliated Ute presumption’s purpose since this is not a case where reliance would be difficult to prove because it was based on a negative. We therefore hold the Affiliated Ute presumption of reliance inapplicable....
Id. at 1163. We agree with the Tenth Circuit’s approach, which carefully maintained the well-established distinction, for purposes of the Affiliated Ute presumption, between omission claims, on the one hand, and misrepresentation and manipulation claims, on the other.
Investors also alleged, and the district court addressed, some omissions in their Third Amended Complaint that do not appear in their Fourth Amended Complaint. As we indicated above, see supra, note 5, where the latter complaint differs from the former, we take the latter as operative because it supersedes the prior complaint. Thus, Investors have alleged no actionable omissions and so the Affiliated Ute presumption of reliance does not apply.11
“ ‘The fraud on the market theory,’ ” as the Supreme Court has adopted it,
“is based on the hypothesis that, in an open and developed securities market, the price of a company’s stock is determined by the available material information regarding the company and its business. ... Misleading statements will therefore defraud purchasers of stock even if the purchasers do not directly rely on the misstatements.... The causal connection between the defendants’ fraud and the plaintiffs’ purchase of [942]*942stock in such a case is no less significant than in a ease of direct reliance on misrepresentations.”
Basic, 485 U.S. at 241-42, 108 S.Ct. 978 (quoting Beil v. Speiser, 806 F.2d 1154, 1160-61 (3d Cir.1986) (alteration in original)). Thus, the theory presumes first that “[a]n investor who buys or sells stock at the price set by the market does so in reliance on the integrity of that price.” Id. at 247, 108 S.Ct. 978. Second, “[b]ecause most publicly available information is reflected in market price, an investor’s reliance on any public material misrepresentations ... may be presumed for purposes of a Rule 10b-5 action.” Id.
The second element of the presumption depends upon the efficiency of the market in which the security trades. See Binder, 184 F.3d at 1064; see also Basic, 485 U.S. at 248 n. 27, 108 S.Ct. 978 (listing as an element of the presumption as “that the shares were traded on an efficient market”); Oscar Private Equity Invs. v. Allegiance Telecom, Inc., 487 F.3d 261, 264 (5th Cir.2007) (listing an efficient market as a prerequisite for application of the fraud on the market theory); In re PolyMedica Corp. Sec. Litig., 432 F.3d 1, 7 (1st Cir.2005) (“Before an investor can be presumed to have relied upon the integrity of the market price, however, the market must be ‘efficient.’ ”); Hayes v. Gross, 982 F.2d 104, 106 (3d Cir.1992) (“Where the security involved is traded in an open and efficient market, [the plaintiff] may ... rely on the ‘fraud-on-the-market theory’ .... ”); Freeman v. Laventhol & Horwath, 915 F.2d 193, 198 (6th Cir.1990) (“[T]he presumption of reliance arising from the fraud on the market theory is only supported by common sense and probability as applied to efficient markets.” (internal quotation marks and citation omitted)). Investors acknowledge that the market for GENI’s shares was not efficient. Normally, that would amount to a fatal concession.
Investors, however, ask us to recognize a new presumption for manipulative conduct cases. Investors, they argue, typically rely on the “integrity of the market,” that is, that no one has destroyed its efficiency by manipulation. This consideration justifies a presumption of reliance, according to Investors, when manipulation allegedly destroys the efficiency of the market, and with it the reliability of the market’s price.
We are chary. No authority required the district court to adopt Investors’ integrity of the market presumption. Indeed, the Supreme Court has adopted a rather restrictive view of private suits under § 10(b), noting that, “[t]hough it remains the law, the § 10(b) private right should not be extended beyond its present boundaries.” Stoneridge, 128 S.Ct. at 773. In Stoneridge, the Court listed the Affiliated Ute presumption and the fraud on the market presumption as the two reliance presumptions it has recognized. Id. at 769. After concluding that “[n]either presumption applifed],” it did not inquire into any other presumption that seemed appropriate, but simply analyzed whether the plaintiffs could prove reliance directly. Id. These passages may not forbid the recognition of new presumptions, but they do illustrate that the district court did not have to recognize this one.
We therefore conclude that the district court did not abuse its discretion in refusing to adopt the integrity of the market presumption. On the contrary, it permissibly declined to certify the class under Rule 23(b)(3) on the ground that individual issues pertaining to the issue of reliance predominate over common ones.
IV
For the foregoing reasons, we AFFIRM the district court’s denial of the motion for [943]*943class certification. Each party shall bear its own costs on appeal.