Actually, unclaimed money is not the same as pre-escheat. Pre-escheat means the claim has not been reported as unclaimed money or property. The best source I have found which supplies complete info for pre-escheat plus all things unclaimed money is www.unclaimedmoney.net
Escheat refers to the money that is transferred to the protective custody of a government trust account by insurance companies, banks, brokerages, trade unions etc, when there is no owner directed activity recorded. It is the same as unclaimed money. For details see the link below:
www.unclaimed.com
www.unclaimed.com