A Silicon Valley start-up founder helped guide the U.S. military’s cloud computing efforts as a Pentagon employee for more than a year, even though he had previously worked for Amazon’s cloud computing division, widely seen as a front-runner for a pending $10 billion cloud contract coveted by four of America’s biggest technology companies, computing giant Oracle alleged in a recent lawsuit.

Oracle alleged in the suit that the start-up founder, a man named Deap Ubhi, had been engaged in business discussions with Amazon while he was still employed at the Pentagon. He left the government late last year and rejoined Amazon.

The possibility that Ubhi was biased toward Amazon as he helped plan high-stakes military procurements has put him at the center of a protracted legal battle involving the Defense Department, Amazon and Oracle. According to court documents he had been engaged in early planning and market research for what is known as the Joint Enterprise Defense Infrastructure, or “JEDI,” which is designed as a departmentwide cloud computing infrastructure for the U.S. military. Oracle, the Redwood, Calif.-based software giant, has filed a lawsuit to block the contract award pending further investigation, arguing Ubhi’s involvement has skewed the process in Amazon’s favor. (Amazon founder Jeffrey P. Bezos also owns The Washington Post.)

While Ubhi worked for the Defense Department, he openly praised Amazon on Twitter. He also cheered the growth of TableHero, the Silicon Valley-based reservation-booking start-up he founded in 2015.

“Once an Amazonian, always an Amazonian. Proud today. Thank you, @JeffBezos,” he tweeted on Jan. 30, 2017, referencing a news article noting that Bezos had pledged to fight President Trump’s immigration ban.

Ubhi did not respond to calls and emails Monday. In response to a list of questions, an Amazon Web Services spokesman said, “in both his previous and current capacity, Deap has worked on the AWS Commercial team and has never supported the AWS Public Sector organization,” while also noting that the company does not comment on pending litigation. An AWS spokesman did not respond to multiple requests to make Ubhi available for an interview.

Heather Babb, a Defense Department spokeswoman, declined to comment on personnel matters because of pending litigation but defended the Defense Department’s handling of the cloud procurement.

“From the beginning, the enterprise cloud initiative has been open, transparent and full,” Babb wrote in an email. “The JEDI Cloud final request for proposals reflects the unique and critical needs of DoD, employing the best practices of competitive pricing and security and is not designed around any particular cloud service.”

The contract has a ceiling of $10 billion over a decade and is expected to confer upon the winner a strong foothold for other opportunities as military agencies use it as a springboard for new artificial intelligence applications. The broader cloud adoption and AI capabilities it is meant to support are seen as important to the Pentagon’s ability to compete with Russia and China for military dominance.

Representatives from IBM, Microsoft, Amazon Web Services and Oracle confirmed that their respective companies submitted bids by the Oct. 12 deadline. An award is expected in April 2019.

From the moment of its public unveiling, the JEDI procurement has been dogged by assertions that it is biased in favor of Amazon Web Services. The online retail giant’s cloud computing unit is widely viewed as a front-runner because it has years of experience handling classified data for the CIA, part of an earlier $600 million contract.

Defense Department officials have emphasized that the department’s broader mission requires it to turn to multiple providers. Even so, officials have been firm in their intention to turn to a single provider for the JEDI contract.

Dana Deasy, the Pentagon chief information officer overseeing the process, said in a recent interview that going to more than one provider for the JEDI contract would “double or triple” the complexity of building an enterprisewide cloud computing capability.

“Starting with a number of firms while at the same time trying to build out an enterprise capability just simply did not make sense,” Deasy said.

Amazon executives have praised that strategy in news interviews, arguing it will help the Pentagon move faster. Executives from IBM, Oracle and Microsoft have opposed the single-award approach, arguing it would force the Pentagon to pay billions of dollars to one company while losing out on innovations happening elsewhere.

Oracle and IBM both tried to overturn the single-award approach even though the Pentagon is months from awarding the contract. Pre-award bid protests from Oracle and IBM were respectively denied and dismissed.

Next, Oracle has taken its case to the Court of Federal Claims, where it has filed a lawsuit against the government. This time the company is pointing a finger specifically at Amazon and the Defense Department for what it called “conflicts of interest” that allegedly weren’t properly vetted during the early planning phases of the JEDI procurement. Amazon later filed a motion to make itself a defendant, arguing that Oracle’s allegations give it an economic interest in the case.

Oracle’s lawsuit focuses on Ubhi’s role, as well as that of Anthony DeMartino, a former chief of staff to the deputy secretary of defense.

According to his LinkedIn page, Ubhi worked as a business development professional for Amazon Web Services for two years starting in January 2014, where he coordinated start-up outreach in the San Francisco area. He had previously founded a company called Burrp!, a restaurant app that became widely used in India.

From August 2016 to November 2017 he worked for the Pentagon’s Defense Digital Service, a relatively new Pentagon agency set up to build commercial tech practices into military operations. Then, according to Ubhi’s LinkedIn profile, he rejoined Amazon as “technical product lead for a yet-to-launch AWS service.” Oracle’s lawsuit also alleged that Amazon Web Services had engaged in discussions with Ubhi about a potential acquisition of TableHero, the start-up he founded, citing internal Defense Department memos that have been placed under seal.

(An Amazon spokesman declined to comment on when exactly Ubhi began his second tenure at Amazon, whether Amazon had acquired TableHero or when the company began employment discussions with Ubhi.)

According to a Defense Department memo cited in court documents, Ubhi recused himself from all JEDI-related deliberations on Oct. 31, 2017, noting that he “may soon engage in further partnership discussions” with AWS. He left the next month. The JEDI contract was in the early planning phases at the time.

Oracle’s lawsuit alleges Ubhi participated in “developing and advocating for the single-award approach” for the JEDI contract. Oracle also alleged that Ubhi “attacked anyone who took a multi-cloud position or advocated non-AWS solutions,” citing emails and Slack messages sent from Ubhi to other officials.

Oracle’s complaint alleges Ubhi exerted significant sway over drafting strategy documents. Court documents filed by Oracle cite an internal Slack message from Ubhi to another official stating, “all industry contacts that have been funneled to me have received a response. I will treat them all equally (unless they are stupid — stupidity gets no equality).”

Other officials appeared to express concern with Ubhi’s support for the single-cloud strategy. Another official allegedly told Ubhi via Slack “I really need to better understand from you why only one provider makes sense,” according to sealed documents cited in Oracle’s legal complaint. Oracle also cited an October 2017 email from one DoD official to another, which said “Deap has a specific way he wants to tackle this [one versus multiple providers] and will be attending in person for this purpose.”

Oracle also criticized the Defense Department’s oversight of the contract, including efforts to vet Ubhi, saying a DoD conflict of interest inquiry “spans less than one page” and “entirely ignored” his subsequent employment at AWS.

“Despite knowing that AWS sought to purchase a start-up company from Ubhi during the JEDI procurement and indicating that Ubhi ‘promptly’ recused himself,” Oracle argued, “the [contracting officer] did not investigate when the communications began, how they started, what AWS offered, etc.”

Oracle asked the Defense Department to delay the awarding of its JEDI contract until a more complete investigation into Ubhi’s roles can be completed.

“Unless and until the agency completes an adequate investigation to determine whether Ubhi’s involvement has impacted the integrity of the JEDI cloud competition, no competition can be free and fair,” the company said.