Treasury Stock
Shares a corporation has issued and then repurchased; treasury stock carries no voting rights, pays no dividends, and reduces the count of outstanding shares.
Outstanding shares = issued shares minus treasury shares. Companies buy back stock to support the price, offset dilution from employee compensation, or signal confidence; if the issuer later resells treasury shares, that is a new sale by the issuer, so it must be registered or qualify for an exemption — registered employee stock plans are a common route.