Interactive Brokers is tightening its exposure to MicroStrategy (MSTR) by gradually increasing the margin requirement to a minimum of 50% by January 13, 2025. This means that if you buy MSTR on margin, you cannot let your margin fall below 50% or you will be hit with a margin call and need to add more money to your account. Other brokerages like Schwab have already implemented a 50% requirement, so this isn’t a huge deal. However, it does suggest that they are preparing for some big volatility ahead.