SAN FRANCISCO — 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.