"How can anyone believe that there was no suicide note left?"
SAN FRANCISCO, Calif. (KGO) -- A vigil was held in Milpitas on Friday for the OpenAI whistleblower researcher who was found dead in his San Francisco apartment last month.
Family and friends held a gathering for 26-year-old Suchir Balaji.
There are a lot of questions about his November 26 death.
Suicide Prevention: Local resources for those in crisis
The Medical Examiner says Balaji died by suicide and there are no signs of foul play, but his parents Poornima Ramarao and Balaji Ramamurthy have doubts and have hired an expert to perform an independent autopsy.
They do not believe their son would have died by suicide.
"I was the last person to talk to him. He was happy more, not depressed or anything. And it was his birthday week," said Balagi Ramamurthy, his father.
"He made plans to see us in January. That was the last phone conversation he had with anyone. He went into his apartment and never came out. How can anyone believe that there was no suicide note left?," said Poorenima Aramarao, his mother.
"And there was nobody else on the scene, that doesn't mean they can just come to conclusion. And we have seen the blood shots in the bathroom, signs of fight in the bathroom."
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Balaji died just three months after publicly accusing OpenAI of violating U.S. copyright law while developing ChatGPT.
His information was expected to play a key part in lawsuits against the company.
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OpenAI has said all of its work is legal under fair use laws.
Vigil organizers say they're honoring Suchir Balaji's bravery, and raising awareness to incorporate accountability in artificial intelligence.
If you or someone you know may be experiencing a mental health crisis, call or text the 988 Suicide & Crisis Lifeline at 988.
The Associated Press contributed to this report