SAN JOSE, CALIF. — A third juror was dismissed in Elizabeth Holmes’ criminal trial on Friday for what the judge said was “good cause.” That leaves only two alternates in a trial that’s expected to last until December.

U.S. District Court Judge Edward Davila told prosecutors and defense attorneys for Holmes that he received an email from juror No. 5 on Friday morning. The judge, along with Jeffrey Schenk, an assistant U.S. attorney, and Kevin Downey, a defense attorney for Holmes, spoke with the juror in chamber.

“The court had found good cause to excuse a juror,” Davila told the courtroom upon his return. There was no explanation given for excusing the female juror.

An alternate juror was selected to join the main bench. The impaneled jury deciding the fate of Holmes consists of eight men and four women.

“The juror raised the issue on their own, so they began to believe their ability to serve as an impartial juror was compromised,” said Danny Cevallos, an attorney and NBC News legal analyst, in an interview. “Apparently the court agreed with them,” said Cevallos, who’s been following the case but was not present in the courtroom.

Holmes’ high-profile trial began in San Jose seven weeks ago. The second juror was removed two weeks ago after revealing that, due to her Buddhist beliefs, she could not in good conscious return a verdict that may send Holmes to prison. Last month, a 19-year-old juror was dismissed for financial hardships.

Losing too many jurors runs the risk of a mistrial. However, Cevallos said that, according to a federal rule, after a jury has started deliberations a judge may permit a jury of 11 to return a verdict.

Holmes has pleaded not guilty to ten counts of wire fraud and two counts of conspiracy to commit wire fraud. Federal prosecutors allege Holmes and her co-conspirator, former company president Ramesh “Sunny” Balwani, engaged in a decade-long multimillion-dollar scheme to defraud investors and patients with regards to Theranos’ blood-testing technology.

Holmes and Balwani were indicted in 2018. Her trial has been delayed multiple times due to pandemic-related challenges and Holmes’ pregnancy. Balwani, who also pleaded not guilty, will face a separate trial next year.

Even in the case of a mistrial, Holmes would not be in the clear.

“A retrial, which the government certainly would do, would put Elizabeth’s life on hold again and drain her accounts even further,” Cevallos said. “So as much as a mistrial isn’t a conviction sometimes you’d rather get to the verdict.”

Following the juror’s departure, a scientist at Pfizer, Shane Weber, took the stand. Weber evaluated Theranos in 2008, and reviewed documents related to the blood-testing technology. He later concluded that Pfizer should not pursue a deal with the company.

In his December 2008 summary of a report, Weber recommended that “Theranos does not at this time have any diagnostic or clinical interest to Pfizer,” but he recommended the company revisit the matter every six months.

Weber’s report was shown to jurors. In it, Weber wrote, “Theranos has provided a poorly prepared summary document of their platform for home patient use with anti-angiogenic therapies.”

Further down, he wrote, “Theranos has provided non-informative, tangential, deflective or evasive answers to a written set of technical due diligence questions.”

Weber told his supervisors in an email in January 2009, that he spoke to Holmes to explain that Pfizer would not be using Theranos’ at-home products for patients.

“I was polite, clear, crisp and patiently firm as she pushed back,” the email said. “She asked for other names at Pfizer to approach and I politely deflected.”

Jurors were shown a version of a Theranos report that Holmes had sent to Walgreens executives with the Pfizer logo on it. Weber testified that Pfizer didn’t approve the use of its logo on the report.

“Would it be fair to say in 2010 or after that Pfizer endorsed Theranos technology?” Robert Leach, an assistant U.S. attorney, asked.

Weber responded, “Uh, no.”

Under cross-examination, Weber told jurors that his report on Theranos was never sent to Holmes.

Also on Friday, jurors heard from Bryan Tolbert, who made an investment in Theranos in 2006 and 2013 through Black Diamond Ventures. The firm, which was founded by by Chris Lucas, invested $5 million in the start-up.

Tolbert told jurors that there was limited information about Theranos at the time, but “it felt like a revolutionary technology and you wanted to preserve to your advantage.”

“Chris and I wanted more information, more financial information, more visibility about what was going on,” Tolbert said. “I certainly thought it was intentional they were trying to keep things under wraps.”

WATCH: Another Theranos insider testifies against founder Elizabeth Holmes