here is a 4 ticket limit for the JohnMayer.com and American Express Presales.
There is an 8 ticket limit per household with a 4 ticket limit in select sections.

Please adhere to published ticket limits. Persons who exceed the ticket limit may have any or all of their orders and tickets cancelled without notice by Ticketmaster in its discretion. This includes orders associated with the same name, e-mail address, billing address, credit card number or other information. By clicking on the "Find Tickets" button, or otherwise using this web site, you agree to the Terms of Use which, among other things, prohibit using automatic processes to access this web site or requesting excessively large amounts of web pages.

Our event provider clients decide at their sole discretion which of their tickets are made available for public sale. The tickets we sell belong to our clients and typically represent only a portion of (and sometimes substantially less than) the total venue seating capacity. On occasion, additional tickets may be released by the event provider as late as the event date.

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