The US Securities and Exchange Commission (SEC) is investigating how Amazon.com Inc. handled employee disclosures on the use of third-party sellers’ data purportedly to boost its own private-label business, the Wall Street Journal reported on Wednesday.

The federal regulator’s enforcement division has asked for emails and communications from several senior Amazon executives, according to the report, which cited people familiar with the matter.

Amazon did not immediately respond to a request for comment, while a spokesperson for the SEC declined to comment on the report.

Amazon has been repeatedly accused of knocking off products it sells on its website and of exploiting its vast trove of internal data to promote its own merchandise at the expense of other sellers. The company has denied the allegations.

Following a series of media reports in 2020, Amazon launched an internal investigation to review whether its employees used sellers’ data to promote Amazon’s private-label business.

The company, however, declined to provide the findings to a congressional committee that earlier investigated the e-commerce major and other technology companies, according to the report.

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