Online publication Investopedia reported this week that eBay Inc. has filed a lawsuit in Santa Clara County, California, against Amazon Inc. The suit accuses Amazon of trying to poach eBay sellers illegally.

According to the media report, eBay claims that beginning in 2015, Amazon representatives created eBay accounts and messaged sellers through the site’s email system to convince users to start selling their goods on Amazon. The action violates eBay’s user agreement, the suit claims.

Investopedia reported that last year, for the first time, more than half of the sales on Amazon.com came from third party sellers.

A spokesperson for Amazon said it is investigating the allegations.