Microsoft Corp said on Monday it was looking into whether Russians bought US election ads on its Bing search engine or on other Microsoft-owned products and platforms, after rival Google said it had discovered such ads on its products.
"We take reports of misuse of our platform seriously. We are therefore investigating and if inappropriate activity is found, we will take steps to minimise such misuse in the future," a Microsoft representative said in an email to Reuters.
Earlier reports said Russian operatives bought ads across several of Google's services without the company's knowledge, in the latest evidence that their campaign to influence US voters was wide-reaching and sophisticated, deploying the technology industry's most powerful tools.
The revelation about Google, made by people familiar with an internal company investigation and first reported by The Washington Post, adds it to a growing list of iconic tech companies used by a disinformation operation that US intelligences services have said was approved by the Kremlin.
Twitter and Facebook already had disclosed some Russian accounts, and US investigators say other companies likely were exploited as well.
Google found that tens of thousands of dollars were spent on ads by Russian agents whose vehicles included Google's YouTube and gmail services, along with the company's signature search engine and its DoubleClick ad network, said the people familiar with the internal investigationwho spoke to WP.
Google, which said last month it had found no signs of Russian interference, runs the world's largest online advertising business, and YouTube is the world's largest online video site.
Adding to the significance of the discovery, the Russian ads bought on Google do not appear to be the work of the Internet Research Agency, the shadowy Russian troll farm linked to previous disclosures by companies. Facebook has said that it, too, has been studying thousands of ads that may have been bought by operatives working somewhere other than the Internet Research Agency.
The revelations add to the evidence that the Russian disinformation campaign had not only multiple targets among US technology companies but also multiple centres of operations.
"We see the Russia presence on social media metastasizing," said Rep Adam Schiff of California, the ranking Democrat on the House Intelligence Committee. "The extent of the Russian presence just continues to grow and grow, and I don't think we yet have any kind of full understanding of just how expansive this presence may have been."
Schiff said congressional investigators will ask the companies "why it has taken them so long to discover the Russian use of their technology and how thorough their forensic effort has been, what the impediments are, and how much work remains to be done, and, of course, most importantly, how are they going to ferret this out in the future".
A combination of efforts - both paid and free posts - reached many millions of people despite the relatively modest dollar totals reported so far.
Disinformation flowed more heavily to voters in battleground states, potentially amplifying the electoral impact, according to Oxford University's Project on Computational Propaganda.
Several independent researchers also have found that the Russian disinformation flowed across platforms and onto the wider Web, taking advantage of technology that allows advertisers to identify potential voters and follow and re-target ads to them based on their political inclinations. The goal was to influence voting behaviour, in some cases by suppressing turnout.
Google's internal investigation found $4,700 of search ads and display ads that the company believes are Russian-connected, and found $53,000 of ads with political content that were purchased from Russian internet providers, building addresses or with Russian currency, people familiar with the investigation said.
Google allows political targeting for two categories - left-leaning and right-leaning - a far more limited set of options than the thousands of ways to slice and dice categories on Facebook. Google has not found evidence that the accounts linked to Russia used its political targeting tools, the people familiar with its investigation said.
Google said in a statement Monday, after The Washington Post first reported on the Russian-linked ads on the company's services, "We have a set of strict ads policies including limits on political ad targeting and prohibitions on targeting based on race and religion. We are taking a deeper look to investigate attempts to abuse our systems, working with researchers and other companies, and will provide assistance to ongoing inquiries."
Facebook said last week that modelling showed that 10 million people saw the Russian-bought ads by the 470 pages and accounts controlled by the Internet Research Agency. But, a Columbia social media researcher, reported soon after that free Facebook content affiliated with just six of those 470 pages and accounts likely reached the news feeds of users hundreds of millions of times.
Twitter has said that it has shut down 201 accounts associated with the Internet Research Agency. It also disclosed that the account for the news site RT, which the company linked to the Kremlin, spent $274,100 on its platform in 2016.
Twitter has not said how many times the Russian disinformation was shared.
Executives for Facebook and Twitter will testify before congressional investigators on 1 November. Google has not said whether it will accept a similar invitation to do so.
Google's probe is in its early stages, WP's sources said. Google is continuing to examine its own records and also is sharing data with Facebook.