A company offering shares to the public in Singapore must issue a document known as a prospectus. Under section 240 of Securities and Futures Act (SFA), all offers of securities are prima facie (accepted as correct, until proven otherwise) according to the prospectus unless the offer is specifically exempted from providing a prospectus.
In reality, you cannot openly sell holding company shares to the general public and via mass media (i.e social media). Doing so is against the SFA and subject to prosecution.
Speak to us if you need to raise capital for your holding company.