Amazon.com has filed 11 lawsuits against online marketers in the US and Canada, alleging they use the Amazon name when sending email advertisements.
The suits seek millions of dollars in damages and are part of a broader action by Amazon to crack down on email forgeries, the Seattle-based online retailer said in a statement.
The companies named in the suits hawked products including home appliances, penis enlargement pills and car warranties, according to Amazon.
Amazon and the New York attorney general's office have already settled with one of the alleged email forgers. Cyebye.com of Brooklyn, New York, had agreed to pay unspecified damages and a $US10,000 fine, Amazon said. Cyebye.com also must refrain from sending email messages using third-party names unless it had express authorisation to do so, Amazon said.
Forging the sender's address in an email is an online trick called "spoofing." It is a problem for Amazon and others that have a trusted domain name and use e-mail to communicate with customers.
The practice was not just spam but consumer fraud, Amazon general counsel, David Zapolsky, said.
Amazon was working with Internet service providers and others to find technical ways to make it more difficult to spoof e-mail addresses, the company said.
In addition, Amazon had set up a special email address, email@example.com, that consumers can use to report spoofing that involves the online retailer.