"For all its ubiquity and convenience, email remains the single most effective and widely used vector of attack. Our State of Email Trust report shows that companies are starting to take email security more seriously, but there's still a long, long way to go."
He praised President Obama's recent executive order that firms share threat data with one another as a "step in the right direction."
In December, Agari looked at email security adoption rates among the UK's best-known firms - none achieved the top 'rock star' rating.
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