# Business Rules When updating products, please bear in mind the following business rules.\ • The 'Brand' parameter won’t be mandatory, if the (SKU) codes in the product catalog are unique. If there are two (SKU) codes with different brands, the change will be reported as invalid.\ • The 'Brand' parameter can be set by ID or Name.\ • The 'SKU' parameter is mandatory and should match with the product code in the catalog.\ Despite the name, the product code set in this attribute works with the "SKU" or "Owncode" product codes from the catalog.\ First, the API will try to find the product using the stored "SKU" attribute/value of the product. If it does not find any product, then it will try to find the product using the stored "Owncode" attribute/value of the product. If it could not find a product either, it will return error code 404 (Not found) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://developers.alephee.com/v2/products/post-methods/business-rules.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.