MIXI rolls out ChatGPT Enterprise to all staff and reaches 80% weekly use in under three months

The problem

MIXI has promoted generative AI use since 2023, but individual tools and pockets of enthusiasm do not change how a whole company works. It wanted every employee to have a safe, supported way to use AI in daily work.

What they built

In March 2025 MIXI introduced ChatGPT Enterprise, OpenAI's business version of ChatGPT, to all employees. That includes full-time, contract, part-time and temporary staff, about 2,000 people as of April 2025. Employees can build custom GPTs, which are small assistants set up for one task. Staff use them mainly to write and edit text, brainstorm, research and check facts, troubleshoot technical problems, and analyse data.

How they did it

MIXI worked with OpenAI on a ChatGPT 101 course for all staff, a workshop for 2025 graduate hires and a hackathon for engineers using OpenAI's Agents SDK. An AI Committee set up in December 2024 oversees adoption, and each division has an AI ambassador. Internal guidelines require that what staff enter matches confidentiality labels. Each department reports its use cases monthly.

Results

MIXI says weekly use reached 80% in less than three months and monthly use exceeded 90%. Employees created more than 1,800 custom GPTs, roughly triple the number at launch. In a survey three months after rollout, 99% of users said productivity improved and 89% said job satisfaction improved. MIXI also uses the survey to project a company-wide time saving (its release says work time is "expected" to fall by about 17,600 hours a month). That figure is an extrapolation from self-reported answers, not a measured result. Individual teams also report gains, for example about 10 minutes instead of 30 minutes to an hour for a legal review of terms of service.