How AI decimated this Prosus company

The collapse in active usage of Prosus portfolio company Stack Overflow over the last three years has been nothing short of spectacular. The repository of coding knowledge, where developers are able to get help from peers on questions, saw the number of user questions per month drop tobelow 3 500in December 2025 (or just under 7 000, when including deleted questions) – a decline of 80% from the prior year. This level is 98% lower than its peak, reached in March 2014, according to company data.

Including deleted questions, its peak was around 300 000 per month at the start of the Covid-19 pandemic. As developers turned to a host of powerful code-writing AI assistants such as ChatGPT, Anthropic’s Claude, Google Gemini and (to a lesser extent) Microsoft Copilot, usage of Stack Overflow fell off a cliff. Prosus purchased Stack Overflow for “approximately $1.8 billion” in June 2021 (the final figure was $1.742 billion, including the $98 million in cash in that unit – this equates to R27.9 billion at current exchange rates).

Given the soaring usage by work-from-home developers (who were physically separated from their colleagues who they would’ve often turned to for help) during the pandemic, this was as close to a full price as the Silicon Valley venture capital funders would’ve been able to get for this asset. They would’ve seen the then CEO of Prosus, Bob van Dijk, and his investment bankers coming a mile away. This only became a “core segment” of the group a year earlier when a number of its education investments “graduated” from its Ventures arm.