Chord symbols sit above the staff, beat-aligned, never in the below-staff text stack

Chord symbols (distinct from roman-numeral analysis) are placed above the staff, left-aligned to the beat where the harmony begins, never sharing the below-staff territory used by dynamics, figured bass, roman numerals, or lyrics.

A chord symbol renders below the staff, colliding with the below-staff stack used by figured bass/roman numerals/lyrics — or renders beat-misaligned relative to the harmony's actual onset.

De facto jazz-real-book/Berklee convention, also implemented by SMuFL's dedicated chord-symbol glyph range and by Dorico/Finale/Sibelius's chord-symbol input systems, which Gradus should follow as the convention musicians expect. Some lead-sheet/pop-arranging house styles place chord symbols differently in specialized contexts, an acknowledged but minority variant.

This rule needs the notated content and the rendered result together — the score says what should happen, the page says whether it did.