Request for recommendations about mobile UX consulting agency in the US

Hello, I’m a UX consultant in Japanese consulting
company, specialized in Web-consulting service, currently providing
the service in East Asia regions, such as Japan, Taiwan, and Mainland

Now we are planning to send some of our colleagues to the US and let
them work in the UX company as the intern.
The purpose is to learn the latest methodology and knowledge about UX from the US company more deeply.

It would be very grateful if we can get a suggestion about suitable companies or persons we should contact to get the chance of the intern.

[Criteria of the companies we’re searching]

  • They are the UX agency (because we’re UX consulting company and intern should experience the consulting project)
  • They deliver consulting services for Mobile UX or digital service design
  • Their project includes not only strategy, but also UI design part
  • They conduct user research in their project
  • They can accept an intern as a project member
  • It is better if they are in San Francisco (because we assume there are many UX companies in San Francisco, but this is not a necessary condition)

We are looking forward to your reply!
Thanks in advance!