Emails and the Mailbox Rule: 21st Century Application of a 19th Century Doctrine
The evidentiary presumption under federal common law that a letter that was properly addressed and mailed will be received by its intended recipient, also known as the "mailbox rule," dates back to the U.S. Supreme Court's 1884 decision in Rosenthal v. Walker. 111 U.S. 185, 193 (1884). In Rosenthal, the court held that the presumption is "a mere inference of fact, founded on the probability that the officers of the government will do their duty and the usual course of business" in delivering the mail to its intended recipient. Id. at 193. The presumption is rebuttable, however: If the intended recipient contends that he never received the letter, then the factfinder must decide the resulting issue of fact.
The mailbox rule often arises where notice is a determinative issue. For example, under the Family and Medical Leave Act (FMLA), an employer is required to notify a covered employee if a leave of absence falls under FMLA. 29 C.F.R. §825.300. In related litigation, the employer can prove mailing and invoke the mailbox rule to establish that the employee received the notice. See, e.g., Lupyan v. Corinthian Colleges, 761 F.3d 314 (3d Cir. 2014). Similarly, under the Employee Retirement Income Security Act (ERISA), an employee may be required to file documents in a timely manner to receive plan benefits. Where the plan administrator denies receipt of the requisite documents, the mailbox presumption may come into play upon proof of mailing. See Schikore v. BankAmerica Supplemental Ret. Plan, 269 F.3d 956 (9th Cir. 2001).