Anthropic’s IPO march began with a Claude Code breakthrough

Last fall, Anthropic was playing second fiddle to Open AI. It had a lower valuation, while Open AI was still drawing much of the attention as the first mover in the generative AI boom. But the dynamic shifted in late November, when Anthropic released Claude Opus 4.5, which gave the company’s Claude Code coding agent a new brain and helped elevate it to the status of “AI killer app.” Arguably, that was the moment that set Anthropic on its path toward a forthcoming initial public offering (IPO). Developers had been using Claude Code to build software for much of 2025, but the tool had shown more promise than truly game-changing results. Opus 4.5 gave Claude Code the intelligence to build an app or feature from end to end, based only on plain-language planning and guidance prompts from the user. Opus 4.5 enabled longer-running agents and better planning and execution workflows. Claude Code got better at discussing a project with an engineer-user, presenting a plan, incorporating feedback, and then carrying out a focused set of multistep tasks to complete a software build. Anthropic sweetened the deal by imposing fewer usage caps, which makes a big difference for software engineers who spend their days deploying multiple agents to build different parts of a project. Just as important, Anthropic changed the way software engineers access Claude Code. Instead of using the tool through their machine’s command line interface, they could now select the Code tab in the Claude desktop app, which includes its own integrated terminal. Under that tab, the company also brought together many of the resources developers normally use, including a file editor for viewing and editing code, code-change review windows, parallel coding sessions for different tasks, and other tools. Anthropic turned Claude Code from a terminal/chat tool into something closer to a full desktop coding environment. “Claude Code is excellent at fixing all those small bugs from old projects. . . . ” tweeted Pieter