Investors are reportedly urging Amazon to stop pressuring workers amid the first-ever vote on unionization by the company’s workers.

Amazon is notoriously anti-union, even going so far as to hire Pinkerton detectives to monitor and impede unionization efforts. The company has also been accused of illegally firing individuals who supported organizing. Most recently, Amazon has made waves with employees, pressuring workers in Bessemer, Alabama to vote against unionization.

According to The Financial Times, via Bloomberg, some of Amazon’s investors have had enough, urging the company to stop interfering with unionization efforts. The group is made up of more than 70 investors, collectively holding some $20 billion of the company’s shares. The comptrollers for the state of New York and New York City, BMO Global Asset Management, Sweden-based Folksam and Ohman Fonder, as well as the Church of England Pensions Board are just a few of the investors in question.

“As these workers seek to organize with [the union] for health, safety, and protection, Amazon’s investors are watching,” New York City comptroller Scott Stringer said, according to the FT. “There is power in their unity and power in labour, and they have my full support as they fight for a safe, fair workplace.”

The investor backlash is just the latest setback Amazon has faced, due to its dealings with employees. The company recently settled a case with the FTC over stealing some $62 million in tips from its Flex drivers. If the company doesn’t make some major changes, it will likely continue to face fallout and backlash from employees, lawmakers and investors alike.