These dietary supplements all contain acai berries.
According to an article from www.courthousenews.com,about 40 companies were sued ,such as FWM Laboratories, CPX Interaxtive, Netalab, Gillmap Ltd., Natures perfection and Minired UAB, in New York Federal Court and  Southern District.
Not only Oprah has sued this companies but also Dr. Mehmet Oz,the one who has made frequent appearances on The Oprah Winfrey Show.
Oprah and Mehmet Oz accused the companies of "capitalizing on plaintiffs' valuable reputation and intellectual property rights to lure consumers into ordering their infringing products on the false premise that they have been tested or recommended by Ms. Winfrey and/or Dr. Oz when they are not."