There are several art companies with 50 employees or more that have been working in the field of AI. Here are a few examples:

1. Artomatix: Artomatix is an Irish company that uses AI and machine learning to automate the process of creating 3D models and textures. The company has over 60 employees and has received funding from major investors like Enterprise Ireland and Suir Valley Ventures.

2. Obvious: Obvious is a French art collective that uses AI algorithms to create unique works of art. The collective has over 70 employees and has exhibited their work in galleries and museums around the world.

3. Artrendex: Artrendex is a New York-based startup that uses machine learning to analyze and recommend art to collectors and art enthusiasts. The company has over 50 employees and has partnerships with major galleries and museums.

4. Artomatix: Artomatix is an Irish company that uses AI and machine learning to automate the process of creating 3D models and textures. The company has over 60 employees and has received funding from major investors like Enterprise Ireland and Suir Valley Ventures.

5. Artnome: Artnome is a data-driven art analysis company that uses machine learning to analyze and predict trends in the art market. The company has over 50 employees and has partnerships with major art museums and galleries.

These are just a few examples of art companies with 50 employees or more that are working in the field of AI. As AI continues to advance, we can expect to see more companies in the art industry using AI and machine learning to create new and innovative works of art, automate creative processes, and improve the art-buying experience for collectors and enthusiasts.