add state law enforcement. States have frequently been allowed to sue in parens patriae to enforce federal statutes, both at common law, see, e.g., Snapp, 458 U.S. 592 (Puerto Rico had standing to sue in parens patriae under the Wagner-Peyser Act and the Immigration and Nationality Act on behalf of it

party without a real interest of its own then it will not have standing under the parens patriae doctrine." Purdue Pharma, 704 F.3d at 215 (quoting Snapp, 458 U.S. at 600); Snapp, 458 U.S. at 602 (distinguishing quasi-sovereign interest from where a State attempts to "pursue the interests of a privat