Meta reported research tax credits totaling about $6.6 billion from 2023 through 2025, rising from $700 million in 2023 to about $2 billion in 2024 and nearly $4 billion last year, according to the senators' letter, which cites the company's regulatory filings. How much of those credits is tied to data center development is not publicly known. By its own estimates, Meta says it expects to spend as much as $145 billion on its AI infrastructure buildout in 2026, twice what it spent last year.

"The federal research credit can be a useful and necessary tool to support our nation's innovation economy and cutting-edge research," the senators wrote. "Subsidizing your AI data center build is not close to meeting this standard."

In an emailed statement to ENR, Meta spokesman Andy Stone said the company has invested $200 billion in research and development over the past five years, including $57 billion in the last year.

"Unlike traditional data centers, AI-optimized data centers are inherently new and require extensive testing and experimentation that cannot be simulated in order to get the design and build right," Stone said. "This is precisely the kind of domestic investment Congress encouraged when it established these tax incentives decades ago."

The statement did not specify whether Meta claims federal research credits for construction expenditures or how the company distinguishes qualifying experimental activities from ordinary capital construction costs—two questions ENR submitted to the company.

Looking for quick answers on construction and engineering topics?
Try Ask ENR, our new smart AI search tool. Ask ENR →

Scrutiny has also spread to the House. A bipartisan group of roughly two dozen lawmakers wrote the U.S. Treasury Dept., raising concerns about Meta's apparent position that expenditures associated with its data center buildout qualify for the research credit, Semafor reported Oct. 15.

Allowing the credit for data center development and construction would "significantly expand the research credit beyond its intended purpose and risk converting an incentive for technological experimentation into a subsidy for capital expenditures that companies would undertake in the ordinary course of business," the lawmakers wrote.

Federal research credits generally require activities intended to resolve technological uncertainty through experimentation. Eligible expenses can include research-related wages, supplies and certain contracted research costs. IRS guidance excludes land, land improvements and depreciable property from qualifying research supplies, while allowing certain experimental pilot-model expenses that independently satisfy the credit's requirements.

The distinction matters as Meta undertakes multibillion-dollar projects incorporating specialized cooling, electrical and power infrastructure designed for increasingly dense AI computing systems.

Meta's Hyperion campus in Richland Parish, La., has grown into a $27-billion development encompassing buildings and long-lived power, cooling and connectivity infrastructure. Meta and funds managed by Blue Owl Capital formed a venture last year to own the project, with Meta providing construction management services.

A Turner Construction-DPR Construction-Mortenson team is building the 4-million-sq-ft campus, which includes extensive modular electrical and mechanical systems and could eventually require 5 GW of power, ENR previously reported. Peak construction employment is expected to exceed 5,000 workers.

Meta also is developing a more than $10-billion, 1-GW campus in Lebanon, Ind., while a separate venture with BlackRock is financing a 1-GW El Paso campus with approximately $14 billion in development costs for buildings and supporting power, cooling and connectivity infrastructure.

In an Aug. 6 interview with podcaster Tom Shaw posted on Meta's website, Rachel Peterson, Meta's vice president of data centers, described portions of the company's current infrastructure program as first-of-kind engineering.

"Some of the things that we're doing have never been done," Peterson said. "They're first of kind from a design standpoint to the power plants that we're putting in on site, to ... the technology that we're using."

The senators' letter says Meta's 2025 annual report acknowledges uncertainty over whether documentation supporting some of its research credits would withstand scrutiny by tax authorities. The disclosure does not identify data center construction as the source of that uncertainty.

Neither the congressional inquiries nor Meta's response establishes how much of the company's research credits is tied to data center construction. Lawmakers are seeking that breakdown and the specific expenses Meta contends are eligible.

Sen. Peter Welch (D-Vt.) separately asked the Internal Revenue Service Oct. 8 to identify companies claiming research credits for AI data center expenses and whether additional guidance or rulemaking is needed.

"The IRS has a responsibility to ensure tax credits are being claimed as intended by Congress," Welch said in a statement.

The senators gave Meta until Oct. 31 to explain its legal justification for the credits, identify the types and amounts of AI data center expenditures claimed and disclose whether accounting or law firms provided opinions supporting the company's position.