(a) Corporate existence.--Upon the filing of the articles of incorporation in the department or upon the effective date specified in the articles of incorporation, whichever is later, the corporate existence shall begin.
(b) Evidence of incorporation.--Subject to the provisions of section 503 (relating to actions to revoke corporate franchises), the articles of incorporation filed in the department, or recorded in the office of the recorder of deeds under the former provisions of law, shall be conclusive evidence of the fact that the corporation has been incorporated.