SpaceX (SPCX) joins the Russell 1000 and other U.S. indexes on Friday, June 26. This inclusion is part of the FTSE Russell semi-annual rebalancing.

The company qualified for the index through a fast-track rule following its June 12 IPO. Passive investment funds must purchase billions of dollars in SpaceX shares to align with the new benchmarks.

This forced buying will likely concentrate around the market close. The event is expected to generate one of the highest trading volume days of the year.