Pinterest on Friday released its prospect, and the document shows how much influence Facebook and Google hold over internet businesses.
Facebook also affected Pinterest the following quarter when the social network made a change in its login authentication system, "which negatively impacted our user growth and engagement during that period," said Pinterest.
"If Facebook or Google quits a single login or is experiencing a bug, we may lose and not be able to restore users earlier using this feature, and the user's growth or engagement may decline," Pinterest said at filing. "Any of these events can damage our business, revenue, and financial performance."
The duopoly is reflected in the market for electronic advertising. Google and Facebook stand for a combination of 59 percent of US digital advertising companies, according to eMarketer.
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