The Federal Trade Commission is investigating Amazon's deal with Apple last fall to add direct iPhone sales to the mammoth e-commerce site.
The Verge reported Friday that the arrangement has harmed small device sellers, some of whom have been interviewed by the FTC as part of the inquiry.
The deal "had the effect of kicking off hundreds of legitimate sellers that were offering low-cost and refurbished Apple products that were no longer for sale by the company itself," the report said.
An FTC spokesperson said the commission has no comment on the report, and Amazon also declined to comment to CRN USA. Apple did not immediately respond to a request for comment.
In early November, Apple teamed up with Amazon to expand the choices for products such as the iPhone that are available on Amazon.com.
"Amazon is constantly working to enhance the customer experience, and one of the ways we do this is by increasing selection of the products we know customers want," Amazon said at the time in a statement. "We look forward to expanding our assortment of Apple and Beats products globally."
The report comes as the House Antitrust Subcommittee has launched a bipartisan investigation of several tech giants, including Apple and Amazon. Meanwhile, a June report indicated that the US Justice Department could lead an investigation into whether Apple has abused its position in the mobile device market to stymie competition.