Sponsors are non-profit organizations designated by the US Department of State to oversee the Summer Work Travel USA and Internship programs of the international participants.

They are required to stay in personal contact with the program participants (telephone or email) and make sure that issues affecting the health, safety and welfare of participants are addressed immediately.

If your students move house or leave their job, the sponsor organization needs to know because the students are their responsibility while in the US.

you can reach the actual and updated  list of Summer Work and Travel Designated Sponsor Organizations