I be willing to bet that most companies have done this.
Samsung were caught out doing it to HTC:
http://www.theverge.com/2013/10/24/5023658/samsung-fined-340000-for-posting-negative-htc-reviews
That's what I was referencing. But to provide context, there's almost nothing Samsung haven't been found doing. They gave a literal briefcase full of cash to a court official on a golf course one time. On another, actually true, one of their employees was caught EATING evidence (which were printed documents). And their attitude to other people's patents is cavalier to put it mildly.
I honestly avoid buying from them in all cases except for SSDs where I can't find a comparable competitor.