The “Domestic Daily” tab on the movie's Box Office Mojo page will be used to resolve this market, specifically the "To Date" column.

https://www.boxofficemojo.com/title/tt6718170/

If any finalized numbers in the "To Date" column (for dates December 31, 2023 and before) show a value of more than $300 million, this market will resolve to "YES"

This market will resolve to "NO" if once the December 31, 2023 "To Date" number is finalized it hasn't reached $300 million, or if the run ends and the movie stops being carried by cinemas without it having reached that point.