Some of the top companies making significant investments in artificial intelligence (AI) technologies are:

1. Google
2. Microsoft
3. Amazon
4. IBM
5. Facebook
6. Apple
7. Baidu
8. Intel
9. NVIDIA
10. Tencent

These companies are investing heavily in developing advanced AI algorithms and technologies such as deep learning, natural language processing, and computer vision, which can be applied to a wide range of industries, including healthcare, automotive, finance, and retail, among others. They are also partnering with startups and academic institutions to advance AI research and development.