Facebook spent $4.8 million, an increase of almost 70% from the same period the year before. The world’s largest social-media company is grappling with a mushrooming list of challenges, including federal and state antitrust investigations and criticism over its handling of users’ personal information and its treatment of political content.

Amazon spent $4 million on lobbying, the most the e-commerce giant has ever spent in a single quarter. The online retail giant, which runs a diverse set of businesses, is fending off criticism from policy makers over its acquisitions and its bid for a highly lucrative Pentagon cloud contract.

Spending by Alphabet Inc.’s Google dropped almost 50% to $2.8 million from $5.5 million during the same period last year as it reshuffles its Washington lobbying operations under Karan Bhatia, the global policy chief who joined the company last year. In September, Google hired former Republican Senate aide Mark Isakowitz to head up its operations in the capital, replacing Susan Molinari. During the second quarter, Google ended its relationship with more than a dozen lobbyists at six outside firms.

The big internet platforms are facing unprecedented scrutiny of their business practices after years of virtual inaction in Washington. Both the Justice Department and the Federal Trade Commission, which share a mandate to enforce antitrust laws, have announced broad reviews of the technology sector — indicating that Facebook and possibly Amazon will undergo parallel investigations by both agencies. That came after reports in May that the two agencies had carved up oversight of four tech giants, with the department taking Google and Apple Inc., and the FTC claiming Facebook and Amazon.

Apple reported spending $1.8 million during the third quarter, up 34% from the same period last year. The company said it lobbied on a range of issues including tariffs, privacy, government access to data and patent litigation.

The House Judiciary Committee is also investigating antitrust issues in the tech sector, including scrutiny of how Amazon treats third-party sellers on its platform. The FTC is also questioning third-party merchants who sell their goods through Amazon, Bloomberg has reported. Facebook and Google are also facing bipartisan antitrust probes by states attorneys general across the country.

The companies’ fortunes are falling in Washington after years of popularity, sparked in part by revelations about how Facebook was exploited by Russian meddling in the 2016 election and broad concerns about their privacy practices.

In July, Facebook agreed to pay $5 billion to the FTC — the largest privacy fine in the agency’s history — to resolve the Cambridge Analytica data scandal in which a consulting firm hired by Donald Trump’s campaign obtained data without users’ knowledge from a researcher who created a personality quiz app on the social network. Google was also fined by the FTC to settle claims it violated children’s privacy on its YouTube platform.

Facebook lobbied on competition, online advertising, a campaign finance transparency bill focusing on digital ads, and federal privacy legislation, among other issues, according to the disclosures, which cover the period ending Sept. 30. Its lobbying touched Congress, the White House, the FTC and the Justice Department.

Google lobbied on global trade, digital advertising, cybersecurity and other issues, according to its filings.

Trade groups representing Facebook and Google have also pushed the U.S.’s proposed trade deal with Mexico and Canada to replace Nafta, which contains several digital provisions the groups favor — including the extension of liability protections for third-party content that internet platforms host. Both companies lobbied on the pact.

That shield is increasingly under threat in the U.S. The leadership of the powerful House Energy and Commerce Committee suggested in an August letter that the liability exemption, which helps the companies avoid a wide range of lawsuits, shouldn’t stay in the trade deal while lawmakers are weighing whether to keep it intact.

Contested Contract

Software giant Oracle Corp. spent $1.7 million in the third quarter, an increase of more than 20% from the same period last year. Microsoft Corp. slightly increased its spending to $2.3 million in the period.

Both companies have been battling Amazon over a $10 billion Pentagon cloud-computing contract in moves that grabbed the attention of the White House. In July, Trump said he was considering intervening after hearing complaints that the bid terms are biased and tainted by conflicts of interest. Defense Secretary Mark Esper has ordered a review of the contract, which is known as the Joint Enterprise Defense Infrastructure, or JEDI. Esper has said there is no “hard timeline” to complete the review.

Oracle has waged a legal and lobbying campaign against the cloud-computing program for about two years. Amazon appears to be fighting back. In June, its cloud unit, Amazon Web Services, hired Trump-connected Jeff Miller to lobby for the company.

The third-quarter reports also showed significant activity on trade and tariff issues as Trump continued his trade war with China. Lobbying efforts to pass the U.S.-Mexico-Canada Agreement, or USMCA, also intensified.

The National Retail Federation, which is helping lead a coalition of trade groups opposed to Trump’s tariffs, showed almost $2.3 million in lobbying spending in the third quarter, up from almost $2 million in the second quarter and $1.9 million in the third quarter last year. A spokeswoman said much of the increase was related to trade and tariffs.

The Consumer Technology Association, whose members include Apple Inc., Amazon and Facebook, reported spending more than $1.6 million during the third quarter — up from $1.1 million in the same period last year.

“As long as the president continues to use tariffs as a weapon, CTA will continue to lobby Congress to exercise its clear authority on trade and tax matters,” Michael Petricone, the group’s senior vice president for government and regulatory affairs, said in a statement to Bloomberg.

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