* Trump bans federal use of Anthropic's AI tool Claude

* Legal scholars question U.S. government's authority to

require the same of military contractors

* Lockheed Martin ( LMT ) to comply

By Mike Stone, Alexandra Alper and Courtney Rozen

WASHINGTON, March 3 (Reuters) - U.S. defense

contractors, like Lockheed Martin ( LMT ), are expected to

follow the Pentagon's order to purge Anthropic's prized AI tools

from their supply chains, government contracting and technology

attorneys said, even though the Trump administration's ban on

their use may fail in court.

The expected exodus from Anthropic was a sign of how quickly

firms adjust to the Trump administration's preferences, as they

seek to win pieces of its trillion-dollar annual budget,

government attorneys said.

Last Friday, capping off a heated weeks-long dispute with

Anthropic over technology guardrails on Claude tools used by the

military, President Donald Trump announced a federal agency-wide

ban on the company with a six-month phase out period.

Defense Secretary Pete Hegseth went further, promising to

designate Anthropic as a supply chain risk to national security

and posting: "Effective immediately, no contractor, supplier or

partner that does business with the United States military may

conduct any commercial activity" with the company.

Anthropic said it would challenge the ban in court.

The move raised immediate legal questions, since none of the

authorities that the Trump administration could use to ban

Anthropic allow it to also bar its general use by defense

contractors, according to lawyers who specialize in technology

and contracting laws.

But the shaky legal basis for the prohibition won't stop

companies that depend on the Pentagon from complying with it,

the attorneys said, as Lockheed Martin ( LMT ) has pledged to do.

"We will follow the president's and the Department of War's

direction," Lockheed Martin ( LMT ) said in a statement, referring to

the Department of Defense when asked about its Anthropic use

following the moves by the Trump administration. "We expect

minimal impacts," the company said, adding that it doesn't

depend on any single AI vendor "for any portion of our work."

With huge government contracts at stake, defense contractors

would be quick to comply with the Pentagon's ban, lawyers said.

"Most companies that do significant business with the

government are hyper-aware of what the U.S. government wants and

they're likely already taking steps to cleanse their supply

chains of Anthropic," said Franklin Turner, an attorney who

specializes in government contracts.

"Regardless of the legal justification, I think the threat

is the point ... it has already done harm, significant harm to

the company," he added, referring to Anthropic.

When asked whether they would comply with Trump's order on

Anthropic, General Dynamics ( GD ), Raytheon parent RTX,

and L3Harris ( LHX ) declined to comment.

The Defense Department did not immediately respond to a

request for comment. Anthropic declined to comment but referred

Reuters to its Friday statement, in which it asserted that the

Pentagon does not have the statutory authority to bar its

contractors from using Claude.

QUICK TO FOLLOW ADMINISTRATION BANS

Defense contractors have complied in the past year with Trump's

other directives regarding their agreements with the government,

according to the news outlet Breaking Defense.

According to the site, they speedily removed references to

Diversity, Equity and Inclusion initiatives last year after

President Trump signed an executive order mandating all agencies

include language in contracts and grant awards requiring any

winner to "certify that it does not operate any programs

promoting DEI that violate any applicable federal

anti-discrimination laws."

Under the authority that the Defense Department is most likely

to use, known as the DOD Supply Chain Risk Authority, the agency

could bar would-be contractors from using Anthropic in their

work for the government, government contracting attorneys said.

However, it would not have the power to ban them from using it

in their business entirely.

Jason Workmaster, a contract lawyer at Miller Chevalier,

described the decision to bar Pentagon contractors from using

Anthropic as a "highly aggressive position."

"If and when challenged, there would be a high likelihood

that DOD would be found not to have the authority to do this,

unless there are facts that we do not know about," he said.

It is not even clear if the U.S. military has the authority to

designate Anthropic as a supply chain risk to bar its own use of

the technology.

The Supply Chain Risk Authority has specific requirements

for what constitutes a supply chain risk, such as the threat

that an adversary may sabotage, introduce unwanted capabilities,

or otherwise "subvert" the technology in order to "surveil, deny

or disrupt" its use.

Meanwhile the Federal Acquisition Supply Chain Security Act

(FASCSA), which creates a similar authority, requires the agency

to follow several steps prior to a ban, such as giving the

business the opportunity to respond and notifying Congress,

among others.

The U.S. government so far hasn't shown publicly that it

satisfied the requirements, said Alan Rozenshtein, a University

of Minnesota law professor who specializes in technology

regulation.

"Capitalism and free markets rely on the rule of law," he

said. "This is the opposite of that."

The Trump administration used FASCSA last year to bar

intelligence agencies from buying products from Acronis AG, a

Swiss cybersecurity and data protection company.