A lock-in period is a specified duration during which investors are restricted from selling, transferring, or redeeming certain financial instruments, such as stocks, mutual funds, or bonds. Lock-in periods are imposed by issuers, investment funds, or regulatory authorities to promote stability, discourage short-term trading, and align investor interests with long-term objectives. Lock-in periods vary in duration and terms depending on the type of investment, fund structure, regulatory requirements, and issuer policies. For example, initial public offerings (IPOs) may have lock-in periods for company insiders or early investors to prevent immediate selling pressure after the stock becomes publicly traded. Similarly, mutual funds or retirement accounts may have lock-in periods to encourage investors to stay invested for a minimum period to receive full benefits or avoid penalties. Lock-in periods help protect investors from market volatility, reduce liquidity risk, and foster commitment to long-term investment strategies, encouraging disciplined and patient investing behavior.