The economic valuation of goodwill is based on an interdisciplinary approach that synergistically considers its legal, accounting, fiscal, and strategic aspects. The controversial concept of goodwill (if positive, badwill if negative) has always divided lawyers, business people, and economists, and is applied in M&A transactions. Digital goodwill is even more slippery, as it refers to the scalable properties of innovative intangibles, whose business models and market comparables are difficult to figure out. Any competitive advantage is intrinsically ephemeral. Goodwill is a residual intangible asset, representing the added value that cannot be directly attributed to any specific identifiable intangible asset. The customers’ portfolio is one of the most critical components of goodwill.