MARK ZUCKERBERG OF FACEBOOK
Facebook was called out for its aggressive acquisition of competitors, such as Instagram, as a way to eliminate competitive threats. But Mr Zuckerberg disagreed, saying Instagram at the time was a photo-sharing app with many competitors rather than a social media phenomenon.
Republican Representative Frank James Sensenbrenner Jr asked if Facebook filtered out political viewpoints and why it set restrictions on the Twitter account of the eldest son of US President Donald Trump for posting a video making false claims about face masks and hydroxychloroquine. Mr Zuckerberg corrected Mr Sensenbrenner, saying it involved the Twitter platform, not Facebook.
MR SUNDAR PICHAI, ALPHABET, GOOGLE'S PARENT COMPANY
Google was heavily scrutinised over its ability to protect user data. In defence, Mr Pichai said: "We today make it very easy for users to be in control of their data. We remind users to go do a privacy check-up. One billion users have done so."
Republican Representatives Ken Buck and Matt Gaetz targeted Google's pulling out of an initiative to help the Pentagon build technology systems while it continued to operate an artificial intelligence lab in China. Mr Pichai denied that Google still worked with the Chinese military and said the company remained engaged with the US defence department in areas like cyber security.
MR JEFF BEZOS, AMAZON
Mr Bezos was questioned on whether Amazon used data from third-party sellers in making sales decision. In response, he said: "We have a policy against using seller-specific data to aid our private label business, but I can't guarantee you that that policy has never been violated."
Democratic Representative Lucy McBath accused Amazon of "systematically" blocking sellers from selling specific products, adding that sellers "use the words like bullying, fear, and panic to describe their relationship with Amazon". In response, Mr Bezos said: "I do not think that's systematically what's going on".
MR TIM COOK, APPLE
For Apple, the spotlight was on its dominance on mobile apps and Apple's App Store. When asked why Apple removed parental-control apps shortly after the company released its own competing version in 2018, Mr Cook said the company was concerned about the "privacy and security of kids" as the technology being used at that time had the ability to "sort of take over the kid's screen and a third party could see it".
Apple was accused of waiving the 30 per cent commission on Amazon's video-streaming service in exchange for better collaboration between the two. Mr Cook argued that "there is a competition for developers just like there is a competition for customers".
