Usually shares are owned by original sole trader. Shareholders may only sell their shares with the agreement of the other shareholders. Restrictions can be made on sales of shares, not allowed to advertise its share. Smaller than public limited companies.
Advantages
Limited liability
Continuity
Separate legal personality
Original owner can take control
Can easily raise capital
Greater status than unincorporated business
Disadvantages
Legal formalities
Capital cannot be raised by sales of shares to general public
Difficult for shareholders to sell shares
End of year accounts must be sent to Companies House available for public inspection, less secrecy