WASHINGTON—A U.S. judge stopped short of labeling Apple Inc. an “illegal monopolist” on Friday, but the closely-watched ruling provides a roadmap for similar claims against the iPhone maker in the future, legal experts said. Ruling on an antitrust case brought by Epic Games, creator of the online game “Fortnite,” U.S. District Judge Yvonne Gonzalez Rogers said Epic did not present sufficient evidence of Apple having unlawful monopoly power in the relevant market, which she defined as “digital mobile gaming transactions.” But the California judge made clear that the decision was limited to the facts before her. “While the Court finds that Apple enjoys considerable market share of over 55 percent and extraordinarily high profit margins, these factors alone do not show antitrust conduct,” Gonzalez Rogers said. “The Court does not find that it is impossible; only that Epic Games failed in its burden to demonstrate Apple is an illegal monopolist.” …