Answer: online banks have different liabilities that allow them to offer high yield savings. AFAIK, the percentage doesn’t not stay put. It is determined by the federal funds rate so it changes when the government changes their rates.
These are considered very safe because they are not market assets. They are more like loans where you’re the creditor to the bank and they pay you back at 6%. On top of that you get FDIC and SIPC protection.
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