OpenAI Changed The Model. Your Company Didn't Notice. That's The Whole Problem.

YPO Technology Network AI Brief · May 13, 2026 · 10m

A week ago Tuesday, OpenAI silently swapped the default ChatGPT model from GPT-5.3 Instant to GPT-5.5 Instant. Most enterprises did not notice. Their sensitive workflows ran on a different model at lunchtime than they did at breakfast — with a different hallucination profile on legal, medical, and financial outputs — and nobody at the C-level was told. Stephen reads the default swap as the cleanest test of where your company sits on a much larger divide: PwC's finding that 74 percent of AI's economic value is being captured by 20 percent of companies.

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