Transaction databases contain the details of thousands of real-life public and private stock sales. They’re used by business valuators when they apply the guideline transaction method. This method — also known as the merger and acquisition method — is a subset of the market approach. It derives a company’s value from prices paid for companies engaged in the same, or similar, lines of business. Selection criteria Valuators start this methodology by filtering transaction databases based on specific selection criteria. These parameters affect which transactions the valuator analyzes. A minor change in the selection criteria can have a major impact on value. The most obvious selection criterion is the subject company’s Standard Industrial Classification (SIC) or North American Industry Classification System (NAICS) code. But valuators also might set parameters...