Senator Bernie Sanders has doubled down on his attacks against retail giant Amazon by introducing a bill called the “Stop BEZOS Act,” referencing Amazon CEO Jeff Bezos. The bill would establish a corporate tax on companies with 500 or more employees, whose employees rely on federal benefits.

"In other words, the taxpayers of this country would no longer be subsidizing the wealthiest people in this country who are paying their workers inadequate wages," Sanders said at a news conference announcing the bill, according to The Washington Post. "Despite low unemployment, we end up having tens of millions of Americans working at wages that are just so low that they can't adequately take care of their families.”

Technically, the bill is called the “Stop Bad Employers by Zeroing Out Subsidies Act”, but it’s no coincidence that the acronym calls out the billionaire CEO.

Amazon is far from the only company in Sanders’s crosshairs, but it seems it has become the poster child for everything the Vermont senator believes is wrong with the labor economy in America. Sanders has been particularly critical of large corporations paying low wages to some of their workers, meaning many of these employees have to depend on government subsidies such as food stamps to get by.

The proposed tax would require large companies to pay back 100 percent of these benefits: if a worker at a large employer receives $300 in food stamps, for example, the employer would be taxed $300. Sanders said this kind of tax would pressure the corporations into paying a living wage, so employees don’t need to depend on government programs.

Amazon has previously fired back at Sanders, saying that he is providing misleading information about how it pays and treats its employees. It is also encouraging current workers to share their stories about why they enjoy working at Amazon, to counter the horror stories workers have shared with Sanders.