American companies are under pressure to be more responsive to their workers, communities and the environment. But US business groups and regulators are trying to gut one of the main tools that shareholders have used to hold them accountable on issues including climate change, pay, diversity, political spending and gun control.

Over the past two decades, shareholder proposals to put specific questions to a vote as part of the annual proxy process have served as a driving force for greater corporate awareness of environmental, governance and social risks. Research by proxy advisers Institutional Shareholder Services credits such campaigns with helping bring about important major shifts in corporate governance practices.

But the US Securities and Exchange Commission is pressing forward with proposals that would make it much harder to use the proxy process to call for investor votes on specific issues. The rule changes would disproportionately hit small investors and their ability to wage multiyear campaigns for improved disclosure and policy changes.