NSO is now looking into whether the use of Pegasus in Mexico violated that agreement.

Facing two lawsuits in the United States by Apple and Meta, WhatsApp’s parent company, NSO is under more pressure than ever to demonstrate that it’s enforcing its own rules. The Biden administration also blacklisted the Israeli company in 2021, concerned about how Pegasus was used to “maliciously target” dissidents across the world.

NSO appealed the decision, but as part of the process, the company is hoping to show that it is preventing abuse.

A senior executive at NSO said that the company had disconnected 10 clients after they broke the terms of their contracts. One of them, the emir of Dubai, used Pegasus to spy on his ex-wife, according to public court records.

If NSO confirms that Mr. Encinas and others were targeted for no legitimate reason by the Mexican military, the company could immediately shut down the institution’s access to Pegasus.

Publicly, Mr. López Obrador’s stance has not changed. After The Times revealed how the Mexican military became the world’s first — and most prolific — user of Pegasus, the president said the armed forces “are respectful of human rights and don’t do spying like before.”

Emiliano Rodríguez Mega contributed reporting from Mexico City.