Customer assets are separate from brokerage assets (due to rule 15c3-3), so if a broker goes bankrupt, your stock shares are unaffected. If securities were lost

Customer assets are separate from brokerage assets (due to rule 15c3-3), so if a broker goes bankrupt, your stock shares are unaffected. If securities were lost due to theft or fraud, the SIPC protects them up to $500,000. To (sort of) answer your question, the SIPC guarantees the number of shares, not the cash value. http://www.finra.org/investors/alerts/if-brokerage-firm-closes-its-doors http://www.finra.org/investors/alerts/if-brokerage-firm-clos...