Premier Cru labeling on French Burgundy wines

[deszor]

Why is it that sometimes the bottles do have the indication clearly that they are Premier Cru whereas sometimes they do not, even though they have clearly been identified with their field or climat? Example: Simon Bize & Fils has these two bottles:
Savigny-les-Beaunes
Aux Grands Liards 1998
Savigny-les-Beaunes 1er Cru
Les Fournaux 1997