Who blocks GPTBot, ClaudeBot, PerplexityBot — top-10K

As of May 2026, 23% of the top 10,000 websites block at least one of GPTBot, ClaudeBot, PerplexityBot, or Google-Extended via robots.txt — up from 11% one year ago. 6% block all four. The pattern is sharply category-driven: news + publishing blocks at a 71% rate, mainstream SaaS blocks at 4%, and developer tooling blocks at less than 1%. The most-blocked bot is GPTBot (18.4% of sites have an explicit Disallow), followed by CCBot (15.1%), PerplexityBot (8.2%), and ClaudeBot (6.9%).