CAT_VALIDATION_ERROR_BRAND_INVALID indicates the brand attribute is empty, too long, or contains disallowed content like store names, generic descriptors, or promotional text. Snap requires the actual manufacturer brand and rejects placeholders such as 'Generic' or 'No Brand'.
Snap Catalog Manager's product schema has format and value rules per attribute. This issue is typically: missing a required attribute for the category, an invalid enum value (e.g., 'XL' submitted where 'M, L, XL' is the valid set), out-of-range numbers, or attributes that conflict across the feed.