Alphabet Inc. (NASDAQ:GOOG) (NASDAQ:GOOGL) shares sank on Thursday following reports that Google is running months behind on its Gemini 3.5 Pro launch as it works to improve the model.

GOOGL stock is down. See the chart and price action here.

Gemini’s Coding Weakness Puts Google Behind Rivals

Bloomberg reported that the release of Gemini 3.5 Pro has slipped by several months as engineers work to improve the model’s capabilities, particularly in coding—an area where rivals like OpenAI and Anthropic have taken a clear lead.

The delay has frustrated employees and raised concerns that Google risks ceding further ground in one of the most commercially critical segments of AI, according to sources familiar with the matter.