The proof-of-stake is a method of securing a cryptocurrency network and achieving distributed consensus through requesting users to show ownership of a certain amount of currency. It is different from proof-of-work systems that run difficult hashing algorithms to validate electronic transactions. The scheme is largely dependent on the coin, and there's currently no standard form of it. Some cryptocurrencies use a combined proof-of-work/proof-of-stake scheme.
On 21 November 2017, the Tether cryptocurrency announced they were hacked, losing $31 million in USDT from their primary wallet. The company has 'tagged' the stolen currency, hoping to 'lock' them in the hacker's wallet (making them unspendable). Tether indicates that it is building a new core for its primary wallet in response to the attack in order to prevent the stolen coins from being used. From the outset, money market funds fell under the jurisdiction of the SEC as they appeared to be more like investments (most similar to traditional stocks and bonds) vs. deposits and loans (cash and cash equivalents the domain of the bankers). Although money market funds are quite close to and are often accounted for as cash equivalents their main regulator, the SEC, has zero mandate to control the supply of money, limit the overall extension of credit, mitigate against boom and bust cycles, etc. The SEC’s focus remains on adequate disclosure of risk, and honesty and integrity in financial reporting and trading markets. After adequate disclosure, the SEC adopts a hands off, let the buyer beware attitude. The Money Market enables the commercial banks to use their excess reserves in profitable investment. The main objective of the commercial banks is to earn income from its reserves as well as maintain liquidity to meet the uncertain cash demand of the depositors. In the money market, the excess reserves of the commercial banks are invested in near-money assets (e.g., short-term bills of exchange), which are easily converted into cash. Thus, commercial banks earn profits without sacrificing liquidity.