Anthropic’s release of Claude Opus 5.5 on September 22, 2026, at $4 input and $20 output per million tokens marked the first price reduction in the Opus line since the $5/$25 debut of Opus 5 in July. The model emphasized improved agentic performance, reduced token usage, and stronger safeguards while maintaining a 1M context window. No announcements or leaks have surfaced for an Opus 5.6 or higher version through mid-October, with recent focus shifting to Sonnet 5.5 and Haiku 5.5 updates plus expanded cybersecurity programs. Traders watch Anthropic’s typical 4–8 week iteration cycles, competitive moves from OpenAI and Google on frontier pricing, and any signals around efficiency gains or regulatory compliance that could trigger the next output-token pricing reveal.