Suit filed on the same day after Apple boots Fortnite from its online marketplace, after Epic added a payment system that let player transactions bypass the App Store system, saving money in the process.
The maker of video game sensation "Fortnite" has sued Apple for the way it rules over the App Store, accusing the iPhone maker of wielding monopoly power.
Epic Games called on a federal judge to order Apple to stop its "anti-competitive conduct" and invalidate the tech giant's rules requiring app developers to pay 30 percent of transactions as the price of doing business in the App Store.
The suit was filed on Wednesday the same day Apple booted Fortnite from the online marketplace, after Epic added a payment system that let player transactions bypass the App Store system, saving money in the process.
"Today, Epic Games took the unfortunate step of violating the App Store guidelines that are applied equally to every developer and designed to keep the store safe for our users," Apple said in reply to an AFP inquiry.
"As a result their Fortnite app has been removed from the store."
Ruling the App Store
Apple has in recent months come under fire for the tight grip it has on the App Store, which is the sole source of applications for its popular mobile devices. The issue came up during a heated congressional antitrust hearing last month.
"Apple has become what it once railed against: the behemoth seeking to control markets, block competition, and stifle innovation," the lawsuit argued.
"Apple is bigger, more powerful, more entrenched, and more pernicious than the monopolists of yesteryear."
Gamers with Fortnite on their iPhones will still be able to play the game, but won't get updates because those would need to come through the App Store.
The Silicon Valley colossus has defended its position as needed to keep applications, and by extension users, safe from hackers and scammers, claiming that its commission on transactions, which can drop to 15 percent in the second year for subscriptions, is earned by minding the shop.
"Epic agreed to the App Store terms and guidelines freely and we're glad they've built such a successful business on the App Store," Apple said.
"The fact that their business interests now lead them to push for a special arrangement does not change the fact that these guidelines create a level playing field for all developers and make the store safe for all users."
Epic's suit, however, accuses Apple of unreasonably restraining trade.
Epic said it is not seeking money or favorable treatment, but instead asking the court order the Apple store rule to be changed for all developers.
Fortnite has been played some 350 million people around the world since its release in 2017, a game where players in a virtual world must survive by searching for weapons and resources while eliminating competitors.
It is also a popular e-sports title in which spectators watch experts players and personalities compete, in some cases for cash prizes.
"Apple imposes unreasonable and unlawful restraints to completely monopolise both markets and prevent software developers from reaching the over one billion users of its mobile devices unless they go through a single store controlled by Apple," the suited contended.
"Where Apple exacts an oppressive 30 percent tax on the sale of every app."