Burned
r/Android
April 2013
Samsung fined for paying people to post fake anti-HTC comments online
Samsung (Taiwan)
What happened
Taiwan's Fair Trade Commission found that Samsung Taiwan had hired writers and students to anonymously post disparaging comments about rival HTC's phones and glowing comments about Samsung's on public forums. Samsung was fined roughly $340,000 for the astroturfing campaign, one of the largest confirmed cases of a major brand faking online sentiment.
The lesson
Fake grassroots praise or planted attacks on competitors are a legal and reputational time bomb; regulators and communities actively hunt for coordinated inauthentic behavior.