A state law saying "arbitration is awesome, but banning class arbitration is against our public policy" still has the effect of finding part of an arbitration agreement unenforceable. The rule effectively changes an agreement from "We agree to arbitrate disputes. No arbitration will proceed on a class or collective basis." to "We agree to arbitrate disputes. Arbitration may proceed on a class or collective basis." I don't see how the fact that the state rule would only render part of an arbitration agreement unenforceable, as opposed to the entire agreement (like the CA rule did), matters. Quoting Concepcion (emphasis mine):

> We differ with the Concepcions only in the application of this analysis to the matter before us. We do not agree that rules requiring judicially monitored discovery or adherence to the Federal Rules of Evidence are “a far cry from this case.” Brief for Respondents 32. The overarching purpose of the FAA, evident in the text of §§2, 3, and 4, is to ensure the enforcement of arbitration agreements according to their terms so as to facilitate streamlined proceedings. Requiring the availability of classwide arbitration interferes with fundamental attributes of arbitration and thus creates a scheme inconsistent with the FAA.

...

> Although we have had little occasion to examine classwide arbitration, our decision in Stolt-Nielsen is instructive. In that case we held that an arbitration panel exceeded its power under §10(a)(4) of the FAA by imposing class procedures based on policy judgments rather than the arbitration agreement itself or some background principle of contract law that would affect its interpretation. 559 U. S., at ___ (slip op., at 20–23). We then held that the agreement at issue, which was silent on the question of class procedures, could not be interpreted to allow them because the “changes brought about by the shift from bilateral arbitration to class-action arbitration” are “fundamental.” Id., at ___ (slip op., at 22). This is obvious as a structural matter: Classwide arbitration includes absent parties, necessitating additional and different procedures and involving higher stakes. Confidentiality becomes more difficult. And while it is theoretically possible to select an arbitrator with some expertise relevant to the class-certification question, arbitrators are not generally knowledgeable in the often-dominant procedural aspects of certification, such as the protection of absent parties. The conclusion follows that class arbitration, to the extent it is manufactured by Discover Bank rather than consensual, is inconsistent with the FAA.

A state law like this would still manufacture class arbitration, so I don't see how it could avoid Concepcion's holding. And the holding that requiring the availability of classwide arbitration "interferes with fundamental attributes of arbitration" seems impossible to work around.

(Also, if there was a possible "backdoor" way of prohibiting class waivers while still complying with Concepcion, I expect California would have tried it already.)

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response to https://news.ycombinator.com/item?id=16162950 (can't directly respond because of the nesting limit):

> Note specifically that it's saying policy judgements cannot override the FAA. It also explicitly says background principle of contract law may affect its interpretation. One of those background principles is traditionally being state law on how contracts are interpreted and what is allowed or not allowed. In fact, that's where all the contract law they talk about is coming from. There is no federal contract law.

But would this state law really be a "background principle of contract law"? It sounds like it would have "a disproportionate impact on arbitration" and "stand as an obstacle to the accomplishment of the FAA’s objectives" (which, according to Concepcion, is somehow incompatible with class arbitration); it's not just some generally applicable rule. Any state law that tries to require the availability of class arbitration is not going to pass Concepcion under that broad test, no matter the vehicle.

There is no federal contract law, but the current Supreme Court has gotten awfully close when it comes to arbitration. One example: in DirecTV v. Imburgia (https://www.supremecourt.gov/opinions/15pdf/14-462_2co3.pdf; unlike the other decisions, this one was not on party lines), the Supreme Court was unwilling to defer to the California Court of Appeals on contract interpretation relating to arbitration.

You should be right, but it's just not something the current Supreme Court will go along with.

> Last i looked, there is pending legislation on this matter, so ...

Do you have a link to that?