Facebook and Instagram parent Meta Platforms has shut down CrowdTangle, a tool widely used by researchers, watchdog organizations and journalists to monitor social media posts, notably to track how misinformation spreads on the company’s platforms.

Wednesday’s shutdown, which Meta announced earlier this year, has been protested by researchers and nonprofits. In May, dozens of groups, including the Center for Democracy and Technology, the Digital Forensic Research Lab at the Atlantic Council, Human Rights Watch and NYU’s Center for Social Media & Politics, sent a letter to the company asking that it keep the tool running through at least January so it would be available through the U.S. presidential elections.

“This decision jeopardizes essential pre- and post-election oversight mechanisms and undermines Meta’s transparency efforts during this critical period, and at a time when social trust and digital democracy are alarmingly fragile,” the letter said.

CrowdTangle, “has been an essential tool in helping researchers parse through the vast amount of information on the platform and identify harmful content and threats,” it added.