The end of ChatGPT's dominance, or its continuation? A recent survey conducted by Surista Inc. (Tokyo) among 400 company employees nationwide revealed the tool usage share among 153 individuals who use AI for their work. ChatGPT secured the top spot with 60.8%, while Google Gemini (49.7%) and Microsoft Copilot (41.8%) closely followed. A significant gap emerged between these and Claude (7.8%) and Perplexity (6.5%), clearly showing a landscape where the "free big three" dominate workplace AI. Furthermore, among small and medium-sized enterprises (up to 100 employees), Gemini (56.1%) is closing in on ChatGPT (58.5%), revealing a structure where the leading player changes depending on company size. Three Key Topics Usage Rate of the Big Three: ChatGPT 60.8% (n=93) / Gemini 49.7% (n=76) / Copilot 41.8% (n=64) — A large gap from 4th place and below. 49.0% of AI users use multiple tools concurrently, averaging 1.82 tools — Shifting from "single choice" to an era of "differential use." Larger companies show higher Copilot usage rates — The impact of Microsoft 365 integration is significant. 1. Overall AI Tool Share (Based on 153 AI Users) ChatGPT: 93 users / 60.8% Google Gemini: 76 users / 49.7% Microsoft Copilot: 64 users / 41.8% Claude: 12 users / 7.8% Perplexity: 10 users / 6.5% Notion AI: 6 users / 3.9% Others: Below 4% The combined share of the big three is overwhelming. The workplace AI market is effectively divided into three by ChatGPT, Gemini, and Copilot. 2. Distribution of Concurrent Tool Usage Using only one tool: 78 users / 51.0% Using two tools concurrently: 52 users / 34.0% Using three tools concurrently: 12 users / 7.8% Using four or more tools concurrently: 11 users / 7.2% 49.0% of AI users use multiple tools concurrently. The average is 1.82 tools, indicating that differential use according to work scenarios is becoming established. 3. Tool Share by Company Size: Gemini Narrows the Gap in SMEs Small and Medium Enterprises (up to 100 employees, n=41): Chat