Former senior national security officials, including two ex-CIA directors and a past NSA director, are backing Apple\n \n (AAPL)’s app store practices as the iPhone maker fights a critical antitrust case. The nearly two-dozen security experts and former US officials argued Thursday in a court filing that proposals to force open Apple’s mobile ecosystem — such as requirements that iPhones be able to install apps from outside the official app store — would harm user and national security. The star-studded list of signatories includes Gen. Michael Hayden and John Brennan, the former CIA directors, along with Mike McConnell, the former director of national intelligence and NSA director. Others signing onto the friend-of-the-court submission include William Evanina, former director of the National Counterintelligence and Security Center; the longtime national security expert Richard Clarke; and various others with past roles at the Pentagon, the White House and the Department of Homeland Security. “Requiring Apple devices to accept third-party apps and app stores necessarily increases the risk of malware on iOS devices, which directly correlates to an increased risk to national security,” the former officials wrote. The filing comes as Apple seeks to convince a federal appeals court to uphold a lower-court ruling that Apple does not run an illegal monopoly in iOS app distribution. The antitrust case, initially brought by “Fortnite”-maker Epic Games, has been closely watched due to its potential to upend the business models of Apple and Google, the world’s largest app store operators. In arguing that Apple was a monopolist, Epic had called for the ability to offer its own app store as an alternative way to distribute iOS apps. In 2020, Epic openly flouted Apple’s developer rules on in-app payments, setting the stage for a legal confrontation. Some of the same proposals demanded by Epic have also been introduced in the form of legislation in Europe, South Korea and the United States. Last week, EU lawmakers announced agreement on a bill that, among other things, could eventually force Apple to permit “sideloading,” or the installation of apps from non-official sources. In Congress, bills such as the Open App Markets Act seek a similar result. “The national security implications of forced sideloading are front and center in debates on these bills,” the former national security officials wrote. “Rather than leave this kind of regulation to Congress, where it belongs, [Epic] invites the Court to jump into the legislative fray. The Court should decline that invitation.” For its part, Epic has also benefited from a slew of high-profile friend-of-the-court briefs. In their own filings, dozens of state attorneys general and the Justice Department weighed in on the case in January. While they did not explicitly endorse Epic, they argued the lower court had misapplied US antitrust law in various ways in ruling for Apple.