Like getting the car on Friday night... Party at the branch. Bank stocks like JP Morgan and Citi rose Thursday on some loosened parental guidance from the FDIC (that's the government agency responsible for making you feel safe about depositing your cash). If your bank goes rupt, the FDIC's got you covered up to $250K per insured bank. With great deposit insurance, comes great responsibility...
One step back, one step forward... This FDIC announcement rolls back the Volcker Rule, which was imposed after the '08 financial crisis. The goal was to ban the types of risky investments that led to big bank failures. Weakening the Volcker Rules gives banks a bit more freedom, but separately they also just got grounded:
For investors, it's kind of a wash... Shareholders value stocks based on expectations of future profits. Loosening of the Volcker Rule could boost bank profits, which could justify higher stock prices. Buuut... the Fed is limiting dividends and stock buybacks, which are drivers of returns for shareholders. The events canceled out: bank stocks jumped on the FDIC news then fell on Fed news.