After report of OpenAI missing targets, one company sees its worst share-price decline in six months

softbank group shares fell sharply in tokyo trading, posting their worst single-day percentage drop in six months. the trigger was a published report that openai missed several internal targets as competition from rival ai labs intensifies. softbank is a major backer of openai, so the news hit the stock directly. the report didn't specify which targets were missed or by how much, but the market reaction was immediate and severe. shares closed down heavily, wiping out weeks of gains. the decline marks the steepest single-day slide for softbank since at least last year. the company has been leaning heavily on its ai investments to drive growth, making it particularly sensitive to any negative signals from the sector.