IRS can get financial info of third parties without notice to third parties [pdf]
> When the IRS conducts an investigation for the purpose of “determining the liability” of a taxpayer...it must provide notice...But once the Service has reached the stage of “collecting any such liability” ...which is a distinct activity—notice may not be required...TL; DR the IRS has to provide notice if investigating, but not collecting.The IRS found Mr. Polselli liable for taxes. It subpoenaed his law firm for "cancelled checks, wire transfer/credit documents, and all other instruments used by Mr. Polselli to pay the firm." They refused, so the IRS subpoenaed the law firm's banks for the same. They co-operated and let the law firm know. (The IRS was investigating whether "money from [Poselli's LLC] was used to pay Mr. Polselli’s account at [the law firm], or to pay others through [the law firm].")This seems reasonable. You're already on notice they're collecting. The subpoenas are targeted and subject to "a test turning on reasonableness." And there is no gag order.Note: I am not a lawyer. Don’t take legal advice from internet comments.