WASHINGTON—The Securities and Exchange Commission on Thursday said it would drop its lawsuit against two cryptocurrency executives who oversaw $1.5 billion in sales of a digital coin known as XRP, in a move that boosts the industry’s battle against traditional regulation.

The dismissal of civil claims against Brad Garlinghouse and Chris Larsen, who were sued for assisting Ripple Labs’s sales, will likely encourage wealthy crypto defendants to fight regulators in court. At the same time, the SEC’s withdrawal from the case preserves its resources for bigger lawsuits it has filed against crypto giants Coinbase and Binance.