At Google I/O 2026, Google launched a lighter-weight Gemini 3.5 Flash model, and CEO Sundar Pichai assured attendees that Gemini 3.5 Pro would follow in June, stating, "We are using it internally. It's showing great improvements. We are still testing and refining it, and it will roll out to everyone next month." As of July 17, the model has not been released. Bloomberg reported that the delay has caused frustration among Google engineers, AI researchers, and managers, who are concerned the company risks losing its edge to rivals Anthropic and OpenAI. Google provided a statement saying it is "currently testing 3.5 Pro, an upgraded Flash model, and other models with partners." Bloomberg suggested two reasons for the delay: bureaucratic issues due to Google's size and concerns that Gemini 3.5 Pro may not be competitive with rivals' recent releases. Since Google I/O 2026, Anthropic released Claude Mythos Preview and later a version called Fable 5 on June 9, OpenAI announced GPT‑5.6 Sol on July 9, and Chinese AI lab Moonshot released Kimi K3, a massive open-source model with 2.8 trillion parameters.