Lloyd's then instituted some major structural changes: corporate members with limited liability were permitted to join and underwrite insurance; no new unlimited-liability Names were allowed to join (although a few hundred existing ones remained); financial requirements for underwriting were changed, to prevent excess underwriting that was not backed by liquid assets; and market oversight significantly increased. Lloyd's rebounded and started to thrive again after the catastrophic losses arising out of the World Trade Center attack, but it faced increased competition from newly-created companies in Bermuda and other markets.