Amazon began investigating reports that some of its employees have been leaking company information in exchange for bribes, according to a report by The Wall Street Journal. The report claims that Amazon employees have been revealing sales information, deleting negative reviews, and offering up reviewers' email addresses in exchange for money from third-party Amazon sellers. Typically, these interactions have been facilitated by intermediaries that seek out Amazon employees who are willing to offer such services.

While some instances have been traced to US employees, the practice is reportedly rampant in China among Chinese Amazon employees and local third-party sellers. Amazon employees in China may decide to participate because their salaries are quite low, and Chinese sellers may pay up in order to get information that can help them better position their merchandise on Amazon or to contact those who have left negative product reviews.

"We hold our employees to a high ethical standard and anyone in violation of our Code faces discipline, including termination and potential legal and criminal penalties," an Amazon spokesperson said in a statement. "We have zero tolerance for abuse of our systems and if we find bad actors who have engaged in this behavior, we will take swift action against them, including terminating their selling accounts, deleting reviews, withholding funds, and taking legal action."

According to The Wall Street Journal's report, payments to Amazon employees can range from $80 to $2,000, depending on the service. Sales information that sellers can pay for includes insight into buyer habits as well as keywords used in product searches. With this information, sellers can try to make their items more appealing to buyers or edit their listings to try to get them on the first page of a product search.

Employees have reportedly been paid to delete negative product reviews, and sellers can pay to get the email addresses of customers who left negative reviews so the sellers can offer discounts or free products in exchange for positive reviews.

The middlemen in these transactions are called brokers, and they often find Amazon employees via the Chinese chat app WeChat. Brokers ask if employees would like to offer such services for cash and then facilitate the interactions between employees and third-party sellers.

It's difficult to ascertain how widespread this practice is—there are more than two million third-party sellers on Amazon, and they account for more than half of all units sold on the site. Amazon has pushed hard to attract new sellers to its site, but the volume of third-party sellers (particularly those in China) will make it more difficult for the company to stamp out all cases of employee bribery. Third-party sellers may find the selling environment even more challenging, not only because of the sheer number of sellers on Amazon, but also because of those who pay Amazon employees to get an edge.

In addition to this problem, Amazon has had to battle fake reviews and counterfeit merchandise on its platform. Fake product reviews still appear on Amazon, even after the company banned incentivized reviews—those posted by buyers who have been given free or discounted items.

Companies have raised their voices against Amazon, saying the retail giant should do more to prevent the sale of counterfeit products on its platform. Amazon rebutted them, stating earlier this year that it has a team that works around the clock against counterfeit products and that it uses machine-learning technology and automated services to spot copyright violations.