Though you can only apply for one entrepreneur visa at the beginning, the number can go up if you form a partnership in future. However, the applicants will be required to demonstrate the input they will be making to the company.
For example, they must demonstrate inherent skills they are adding and capital injection. The immigration department will review such applications depending on the status of the company since the pioneer got the first entrepreneur visa. It will be particularly important that the new entrepreneur visa applicant is conversant with the business model and is in agreement with the management about his contribution.