Change of Visa Sponsor also known as Change of Employer or Change of Work Sponsorship. 

If you are currently working in Hong Kong on an employment visa and wish to change jobs, you must first obtain an approval from the Hong Kong Immigration Department by filing an application for Change of Visa Sponsorship. The application must be approved by the Immigration Department before starting a new employment.

The application procedure is similar to a brand-new work visa application, but if the new employment is within the same field or industry, and the general circumstances of the applicant remain unchanged, the application should be straightforward. 

Points to note for applicants:

1. Applicant must be physically present in Hong Kong.
2. Applicant must possess a good educational background. Normally it is preferable to have at least an undergraduate degree in the relevant fields. However, in the absence of such a degree, documentary evidence of good technical qualifications, relevant professional abilities, achievements and experience may suffice.
3. Applicant has resigned from his/her last employer with a release letter (stating applicant’s last employment date).
4. There is a genuine job vacancy at the new employing company.