The rules are found in the controversial Children's Online Privacy Protection Act (COPPA). The alleged breach relates to reviews posted on the web site by children under 13 without parental consent, or containing details that may identify the children.
In terms of COPPA, web sites that collect children's personal information must provide a parental privacy notice, a mechanism to obtain verifiable parental consent for the collection of children's information, a system for parental review and deletion of children's information, and security and confidentiality requirements.
Chris Hoofnagle of the Electronic Privacy Information Center, said: "Amazon.com clearly markets its products to children, but has not complied with the privacy responsibilities that accompany such activities."
The complaint does not contend that any child has been harmed as a result of the postings.
Amazon.com spokesman Bill Curry admitted to CNet News that a glitch in its software meant that the children's review form, designed to keep the children's identity secret, did not always work properly but added that this is being fixed.
He acknowledged that sometimes children are "writing reviews and putting inappropriate information in reviews like a street address," but added, "When that happens and gets through the system, we remove it as soon as we're aware of it, and that's a longstanding policy."
Amazon.com's contention is that the action is groundless. Curry stated, "Amazon.com is not a site directed at children."
The site's privacy policy specifically states: "Amazon.com does not sell products for purchase by children. We sell children's products for purchase by adults. If you are under 18, you may use Amazon.com only with the involvement of a parent or guardian."
The FTC has still to comment on the case, which could be influential in determining whether or not a US site is considered to be targeting at children.