What Happens to Your Investments If Your Stock Broker Goes Bankrupt?
https://www.thebalance.com/stock-broker-goes-bankrupt-358091
The Securities Investor Protection Corp (SIPC), protects clients cash and securities, such as stocks and bonds that are held at troubled financial firms. However, commodity contracts, limited partnerships and fixed annuities contracts are ineligible for SIPC protection. Understand that there are limits per customer account that the SIPC may cover up to $500,000 of which $250,000 may be in cash. Check to make sure the firm you are dealing with is a member of SIPC. Practically all national firms of repute are but it will take only a few seconds to verify so it's worth doing.
Many firms have their own supplemental insurance, as well, which covers client assets in the event of a financial failure. Additionally, firms are required to have a net capital reserve.
It is a good practice to maintain organized records of your securities and your accounts as this will help you should the brokerage firm you are dealing with go out of busines