Elon Musk has reasserted his statement that his brain implant startup Neuralink Corp had never caused the death of a monkey, which while may be technically true, skirts around the fact that at least a dozen monkeys died after receiving chip implants.

At the New York Times Dealbook conference on Wednesday, Musk repeated a claim he made earlier this year on X, the social media site he owns, that Neuralink used monkeys that were already close to death for its early experiments.

The post echoed a statement on Neuralink’s website last year that animals were selected that “may not have proper quality of life due to a pre-existing condition”.

The statement referred to two monkeys that were euthanised at planned end dates, and six that were euthanised on medical advice from the veterinary staff at UC Davis, where Neuralink was conducting its primate work at the time.

The Physicians Committee for Responsible Medicine, an anti animal-experiment group, obtained public records from UC Davis that it says showed 12 monkeys died after being implanted with Neuralink’s device.

Neuralink has since built its own facilities for monkeys in Fremont, California. On Wednesday, Musk described them as a “paradise”. A Bloomberg BusinessWeek article in November said the facilities are spacious, with toys, playground equipment and TVs.

Advocates of animal research for medical devices say the research brings lifesaving devices to market without harming humans. Opponents say the research is cruel and often could be conducted in other ways.

 - Bloomberg