Marc Andreessen says AI is already a better doctor than 99.99% of humans —  Mark Cuban says AI healthcare just means more 'delay and deny.' Here's why

Then he went straight for the businesses sitting between patients and their doctors, which, he warned, are building AI agents designed to “delay and deny.”

On July 12, Marc Andreessen, a venture capitalist, was celebrating an AI model that scored better than real doctors on a blind test, with a post quoting Sam Altman’s similar assertion.

Cuban’s rejection wasn’t against the score itself, but was aimed at what the two were celebrating, because of what happens after a good diagnosis reaches an insurance company, where the same industry is already using AI to slow claims down rather than pay them out.

“25 pct or more of a doctor’s time is spent dealing with conglomerates that do all they can to make the doctor’s care more difficult and expensive, for both the doctor and patient,” Cuban replied in a quote on X.

What sparked the public disagreement

On July 10, Karan Singhal, who leads OpenAI’s health research team, posted results from the company’s newest model family, GPT-5.6. In blinded reviews, physicians rated GPT-5.6’s answers to a set of patient-facing and clinician-facing health tasks.

And these were cases picked specifically because they had stumped earlier OpenAI models. The AI came out ahead by a wide margin: Physicians rated its answers as flawless between 19.8% and 23.9% of the time, depending on the variant, compared with just 10.4% for the physician-written responses.

OpenAI CEO Sam Altman reposted the findings on July 11. Andreessen amplified it the day after with a one-line verdict: “AI is already a better doctor than 99.99% of human doctors.”

This led Cuban to reply with skepticism the same day. His perspective reflects a massive gap between tech industry hype and actual patient reality. A West Health-Gallup Center on Healthcare in America survey released April 15 found that one in four U.S. adults has turned to AI at some point with a health question.

Among those who had used one in the past 30 days, only 4% said they strongly trust its accuracy and 11% said an AI tool had given them advice they believed was unsafe. Cuban’s reply landed in that gap because he knew that in the real world, patients aren’t just worried about whether the AI is smart enough; they’re worried about who is pulling its strings.

Why Cuban says the benchmark misses the point

Cuban’s argument starts with a number of his own: He says a quarter or more of a doctor’s working day already goes to fighting insurers, pharmacy benefit managers and other intermediaries, not treating patients. Handing doctors a faster AI assistant doesn’t remove that friction, he argued. It just guarantees the businesses on the other side build faster AI of their own, tools designed to slow down and reject claims rather than approve them.

Cuban says this is already happening. Hospitals, he says, pay outside revenue cycle management firms — companies whose whole job is chasing down the money insurers owe — as much as 10% of revenue for the service. He also likened where this is headed to the old Mad magazine cartoon where two spies keep building sharper weapons against each other and neither one ever wins.

Actually, there’s a real-world test case sitting in Cuban’s own investor portfolio. He’s an investor in Claimable, a startup that uses AI to write appeal letters for patients whose insurance claims get denied. The startup counts Cuban among the backers behind its $10 million in funding, according to Inc., and Bloomberg reported that roughly three out of every four people who appeal through it win a reversal.

In other words, patients are arming themselves with AI appeals, and insurers have every reason to answer with AI denials — Cuban’s warning, running in miniature.

And most people never get that far. On Affordable Care Act marketplace plans, for instance, not even 1 in 100 denied claims was challenged by patients in 2023 — and among those who did push back, insurers stood by 56% of the denials, according to KFF, the nonpartisan health policy research group that analyzed the federal claims data.

Bloomberg’s reporting on Claimable put a face on that math. One user, a patient managing a chronic inflammatory condition, had relied on the same infusion drug for more than half his life. When his employer switched insurers, the new carrier pushed him toward a cheaper alternative, and a single missed dose during the dispute was enough to trigger a painful flare-up.