If you have a company in Hong Kong, and you would like to specify the business nature, you will need to file an IRBR200.
IRBR200 is Notification of Commencement of Business by Corporation issued by Inland Revenue Department.
You will need to file IRBR if you have a Hong Kong Limited company
1) when the date of business commencement is different from the date of incorporation of your company
2) to Inland Revenue Department within 1 month since commencement of business
3) to record changes in the company
You need to provide:
1) Business Registration Number
2) Name of Corporation
3) Business Commencement Date
4) Business Description and Nature
5) Business Address
The form has to be signed by director, secretary or manager of the company.
Sample form: http://www.ird.gov.hk/eng/pdf/irbr200.pdf