Thrust into the spotlight as a result of Edward Snowden’s leaks, these industry leaders historically haven’t voiced loud support for restraining the NSA’s legal authorities to collect data. But many tech firms’ third-quarter lobbying reports, filed Monday night and totaling millions of dollars, demonstrate Silicon Valley is devoting more of its bandwidth to an emerging surveillance debate that could affect many companies’ bottom lines.

Even Washington-wary Apple reported lobbying between the months of July and September on topics “related to government requests for data.” Never before has the Cupertino, Calif.-based iPad maker explicitly talked up that topic here in the Beltway, according to a review of its previous filings. The company spent almost $1 million on lobbying during the third quarter — its most in D.C. to date — to lobby on a range of policy issues.

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Apple and Microsoft couldn’t immediately be reached for comment on their surveillance lobbying; both Facebook and Google declined to address it directly.

The companies’ aim with the new D.C. effort isn’t entirely clear. Silicon Valley to date hasn’t pushed to restrict the NSA’s ability to reach into the Internet’s backbone for foreign suspects’ communications. Instead, the tech companies mostly have made the case for more transparency — the need for better numbers and clearer documents that show how often the government seeks data from them and when.

But continued revelations about U.S. surveillance have raised the potential for new regulation of Internet companies in Europe and beyond. That’s causing headaches for tech companies that store and swap data overseas. Any changes to U.S. surveillance law consequently could have broad impact on business, and Silicon Valley is closely monitoring the congressional action.

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For its part, Google racked up a lobbying tab of $3.3 million between July and September, as the search company pressed regulators on a range of issues from patent reform to cybersecurity to online privacy. But the company also disclosed it had lobbied congressional offices on two high-profile surveillance reform bills — one by Senate Judiciary Committee Chairman Patrick Leahy (D-Vt.), the other chiefly written by Sen. Ron Wyden (D-Ore.). Both would curtail the NSA’s authority.

Google hasn’t taken a public position on whether and how Congress should restrict the NSA’s surveillance capabilities. Asked again Tuesday, the company declined to elaborate. At the moment, Google is emphasizing its transparency push, having joined with Microsoft, LinkedIn, Facebook, Yahoo and others in fighting the feds to reveal more data about the number of times the NSA makes surveillance requests.

Facebook has in the past convened discussions with key lawmakers on the transparency of national security-related orders. The social network’s $1.4 million lobbying tab from the most recent quarter, however, includes one addition: “FISA-related reform,” a reference to the Foreign Intelligence Surveillance Act. Earlier this summer, Microsoft’s lobbying reports reflected a push for more FISA transparency. Months later, though, its new lobbying report reflects $2.23 million of influence spending on transparency as well as government data collection and FISA court reform, among other issues.

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Apple shelled out $970,000 for D.C. lobbying in the third quarter, the most the company has spent in any three-month period here. To date this year, the company has spent $2.38 million in Washington, compared with about $1.4 million by this time last year. As it launched its first-ever lobbying push on government data collection, Apple also pressed for smartphone location privacy protections and patent reforms in the third quarter.

Yahoo, Adobe and LinkedIn also specifically mentioned lobbying on the Foreign Intelligence Surveillance Act, the third-quarter reports show. The Information Technology Industry Council, which represents a broad swath of the tech set, similarly includes the acronym “FISA” in its most recent lobbying disclosure.

Even Twitter, which has not been implicated in the NSA revelations and hasn’t faced the same public scrutiny as its technology cousins, devoted some of its $40,000 in lobbying money over the past three months to a slew of pending FISA reform bills.