New to the forum and had a little hunt for the answer to this but couldn’t find an answer, maybe there is a thread already on cross compatibility ,
anyway, Does Dorico save into a fomat that can be opened by earlier versions of Sibelius ?
Dorico exports MusicXML, which is a compatibility format shared by most softwares that work with music notation.
Muman, to follow up to LSalguerio’s comment: search the forum for “XML.” You’ll find that XML is occasionally (rarely, but sometimes) poor, usually adequate, rarely perfect. Dorico imports XML better than it exports. Some users are pleased with its functionality, some are not.
I suggest some testing of your scores with your typical included elements before you rely on it for something important.
And there’s always MIDI export as well ( though XML is of course better)…