Twitter believes the bitcoin scam to be a "coordinated social engineering attack" that targeted some of its employees that had administrative access.
Jack Dorsey said internet advertising is "incredibly powerful and very effective" but comes with "significant risks to politics".
Says the company hadn't thought 'cohesively' of a solution to harassment
The demographic information marketers rely upon for effective targeting and measurement are demonstrably inaccurate, says the head of social insight at OgilvyOne
Twitter's chief executive, Dick Costolo, is leaving his role on 1 July and will be replaced by the co-founder and chairman, Jack Dorsey, on an interim basis.
The previous recipient of the Award was Eric Schmidt, executive chairman, Google
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