Abstract: System, device, and method of protected electronic commerce and electronic financial transactions. A method includes: analyzing (i) content of an online destination that sells an asset to an end-user, and (ii) data about ownership in the online destination, and (iii) meta-data about that content; and determining that an offering to sell that asset to the end-user is fraudulent. The system further provides digital tokens or crypto-currency, that end-users should pay in order to submit a user-report about a possible scam. The collected crypto-currency tokens are used by the system, to reward a user that submitted a scam report that turned out to be correct, to fund operations of a fraud-prevention entity, to fund guarantee payments to defrauded end-users, and for other purposes. The system generates authenticity stamps for online venues and for crypto-currency wallets that are determined to be legitimate.