Sentence:  It is, effectively, the opposite of so-called "<WSD>brandalism</WSD>" which is where advertisers have no control over how, where and when their branded communication is sabotaged. / For example, billboards in New York for Apple's iPod music player were defaced by one disgruntled customer with the words "iPod's unreplaceable battery lasts only 18 months" after he discovered it would cost more to buy a new battery than to purchase a new iPod. 
Meaning of the word marked with <WSD> tags:  The deliberate defacement of corporate iconography, generally for purposes of protest, parody, or social commentary.