A friend of mine (who gambles for a substantial larger amount than I do) was recently asked for proof of Source of Wealth. I looked into this and figured I'd share what I found out (sharing is caring!). Generally it's just an extra part of verification, focusing mainly on tackling money laundry in the online gaming industry. When requested, you have to provide the casino with proof of where your money came from, for example copies of payslips, inheritance money, previous casino winnings etc. Although we've all kind of gotten used to sharing copies of passports/id cards and other personal information, it seems that the SOW check in particular is sparking quite a discussion about how far casinos can go. Problem being - it's not necessarily the casino itself that requests these documents, but rather gaming authorities that demand casinos to take responsibility in preventing illegal activities from happening under their watch. Personally I wouldn't be to happy about having to send my payslips either, but I guess it all depends on how much I like and trust the casino that's requesting the SOW check as well as how big my balance is.