WATCH LIVE: Lawmakers to question the CEOs of Apple, Google, Facebook, and Amazon

• The CEOs of Apple, Amazon, Facebook, and Google's parent company Alphabet are all testifying today before the US House of Representatives' Antitrust Subcommittee.
• It's extremely rare for one of the tech giants' CEOs to testify before Congress, let alone all four. The historic testimony comes as the subcommittee nears the end of an investigation into whether the tech companies have too much control over the market or unfairly edged out competitors.
• The hearing is scheduled to begin at 12 p.m. EST. Follow along here for live updates.

The CEOs of four of the world's biggest tech companies are testifying before Congress Wednesday to defend their companies' growing power.

Amazon CEO Jeff Bezos, Apple CEO Tim Cook, Facebook CEO Mark Zuckerberg, and Sundar Pichai of Alphabet, which owns Google and YouTube, will testify as part of an ongoing investigation by the House Judiciary's Antitrust subcommittee into whether the tech companies used their control of the market to unfairly edge out competitors.

The subcommittee has held hearings with smaller competitors in recent months, many of whom accused the giants of monopolistic practices.

All four CEOs defended their companies by arguing that they still face fierce competition, and that their massive size helps the tech sector by providing platforms for smaller businesses, according to prepared remarks published ahead of their testimony.

In addition to questions about antitrust, lawmakers are expected to press the CEOs on hot-button issues like the spread of misinformation on their platforms, their treatment of President Donald Trump, and their practices during the COVID-19 pandemic.

Follow along here for live updates during the CEOs' historic testimony.