Facebook has lost a major advertiser, UniCredit SpA, which has severed all ties alleging that the social media giant hasn't acted ethically, reports Bloomberg - which notes that "other large companies" may follow suit.

CEO Jean Pierre Mustier says the bank maintains that Facebook hasn't acted properly, and the Italian financial group will no longer have any type of business relationship with the Menlo Park, CA company.

Mustier was referring to business activities including advertising and marketing campaigns, a spokesman for UniCredit said. The bank currently has a swath of Facebook accounts -- which are regularly updated. -Bloomberg

Facebook has come under intense scrutiny for failing to safeguard user data amid the Cambridge Analytica data harvesting scandal, revealed in March by The Guardian and The New York Times. The data from up to 87 million users, and possibly more, was found to have been "harvested" via the psychological profiling app "Thisisyourdigitallife" - which was created by two psychologists (one of whom currently works for Facebook), and was specially designed to collect and share information.

Despite Facebook's attempts at damage control, UniCredit says they're done with the social media giant - and there have been others. Unilever UV and Sonos Inc. have also threatened to pull ads.

In late July, Facebook’s shares fell over 20 percent after second-quarter revenue showed the first signs of user disenchantment in the midst of public scandals over privacy and content. The company has been under fire following revelations that personal information on as many as 87 million users ended up in the hands of Cambridge Analytica, a political consulting firm that worked on Donald Trump’s presidential campaign. Mozilla Corp., which develops the Firefox web browser, said in March it would pause its ads from appearing on Facebook as a result. -Bloomberg

Was UniCredit's decision really based on Facebook's ethics? Or was the data harvesting scandal perhaps a convenient excuse to disengage from an advertising model that wasn't worth the expense?

In late 2016, Proctor & Gamble cut $200 million in digital ad spending - including scaling back targeted ads from Facebook. In March, the company contended that too much digital ad spending is "a waste."

Once armed with more measurement data, P&G discovered that the average view time for a mobile ad appearing in a news feed, on platforms such as Facebook , was only 1.7 seconds. The Cincinnati-based company also realized some people were seeing P&G ads far too many times. -WSJ

"Once we got transparency, it illuminated what reality was," said P&G's chief brand officer, Marc Pritchard. Ad fraud was another concern.

About a year ago, Mr. Pritchard publicly issued an ultimatum for tech companies to clean up the digital ad ecosystem or it would cut spending. He called on the industry to fix the rampant digital ad fraud and asked tech giants such as Alphabet Inc.’s Google and Facebook Inc. to implement safeguards to prevent ads from appearing around controversial content and to allow independent verification of their ad measurements. -WSJ

Whatever the case, Facebook has now lost a major corporate advertiser - will others follow suit?