The debate surrounding antitrust laws and the monopoly power of major tech companies continues to heat up in Congress, even though members of both parties have accepted political donations from, and own stock in, a variety of Big Tech firms.

Why it matters, per Axios' Scott Rosenberg: For years, the biggest tech companies have been donating through PACs to lawmakers of both parties and building extensive lobbying operations in Washington in preparation for this moment. As legislators weigh new regulations, the firms will learn what kind of influence, if any, their investments have earned.

Driving the news: Regulators on both sides are now "beginning to probe whether the biggest tech companies' handling of consumer data represents an unfair form of competition," Axios' Margret Harding McGill writes.

Worth noting: The numbers from OpenSecrets don't represent money directly donated by the companies themselves. Rather, they're the sum totals from the company's PACs, owners, individual employees and their immediate families. The totals may include subsidiaries and affiliates.

By the numbers: During the 2018 midterm elections, donations from Apple, Google-owner Alphabet Inc., Facebook, Amazon and Microsoft totaled more than $500,000 to candidates on the House Judiciary Committee — with Alphabet Inc. donating the most.

Rep. Zoe Lofgren (D-Calif.) received the largest amount, totaling $89,400, and she accepted a donation from every Big Tech company listed above.

(D-Calif.) received the largest amount, totaling $89,400, and she accepted a donation from every Big Tech company listed above. House Judiciary Chairman Jerry Nadler (D-N.Y.) received a total of $53,708 in donations from Alphabet Inc., Facebook and Microsoft.

(D-N.Y.) received a total of $53,708 in donations from Alphabet Inc., Facebook and Microsoft. Ranking member Doug Collins (R-Ga.) received $21,500 in donations from Microsoft and Alphabet Inc.

(R-Ga.) received $21,500 in donations from Microsoft and Alphabet Inc. Rep. David Cicilline (D-R.I.) received a total of $4,000 from Google.

Key House Judiciary members who own tech stock:

House Speaker Nancy Pelosi (D-Calif.) doesn't sit on the Judiciary Committee, but she and her husband own at least $8.4 million worth of tech stock, according to Morning Consult.

The bottom line: Donations from tech companies and employees were substantially higher in 2018, a midterm election year, than in 2016, a presidential election year. Companies are likely to donate more during the 2020 elections.

For example, Apple donated $144,994 to House candidates in 2016, and donated $290,589 to House candidates in 2018.

What's next: The House Judiciary Committee has requested documents from Alphabet, Amazon, Apple and Facebook as part of an antitrust investigation. The committee says it's received some but not all of the requested documents.

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