https://www.theguardian.com/technology/2017/oct/24/twitter-transparency-political-ads-russia-us-election-trump

‘Transparency center’ offers visibility into who is behind ads as Senate investigates Russia’s used of social media to spread propaganda during election

Twitter has announced the launch of an advertising “transparency center” with stricter rules for political ads in the wake of revelations that social media sites were used to spread Russian propaganda during the 2016 US presidential election.