ISO 10668: Brand Valuation, identifies 3 approaches to brand valuation: the market approach, the cost approach and the income approach.
The ISO Standard lists the following income based methods of determining the cash flow attributable to a brand.
Direct methods (primarily using revenue)
Indirect methods (primarily using profit)
Brand Finance uses the Royalty Relief method for its public rankings, however frequently uses other methods for clients to suit their specific need and situation.