46 UNITED STATES V. MOHAMUD United States v. Heckenkamp, 482 F.3d 1142, 1146 (9th Cir. 2007) (quoting United States v. Lifshitz, 369 F.3d 173, 190 (2d Cir. 2004) (citing Guest v. Leis, 255 F.3d 325, 333 (6th Cir. 2001))); see also Guest, 255 F.3d at 333 (“[Users] would lose a legitimate expectation of privacy in an e-mail that had already reached its recipient; at this moment, the e-mailer would be analogous to a letter-writer, whose ‘expectation of privacy ordinarily terminates upon delivery’ of the letter.” (citation omitted)). It is true that prior case law contemplates a diminished expectation of privacy due to the risk that the recipient will reveal the communication, not that the government will be monitoring the communication unbeknownst to the third party. See, e.g., United States v. Miller, 425 U.S. 435, 443 (1976); United States v. White, 401 U.S. 745, 752 (1971); Hoffa v. United States, 385 U.S. 293, 302 (1966). While these cases do not address the question of government interception, the communications at issue here had been sent to a third party, which reduces Mohamud’s privacy interest at least somewhat, if perhaps not as much as if the foreign national had turned them over to the government voluntarily. See also Hasbajrami, 2016 WL 1029500 at *11 & n.18 (observing same distinction). Thus, Mohamud’s interest in the privacy of his communications received by the overseas foreign national is diminished. iii. Privacy Protecting Measures An important component of the reasonableness inquiry is whether the FISC-approved targeting and minimization measures sufficiently protect the privacy interests of U.S.