<p>This whitepaper proposes the <strong>Brand Capital Index (BCI)</strong>, an open methodology that extends brand valuation from a single financial dimension to a three-dimensional time-series indicator.</p> <p>The BCI formula is: <code>BCI = α·FBV + β·SCV + γ·AIV</code>, where α + β + γ = 1 and BCI ∈ [0,100]. The three components are:</p> <ul> <li><strong>FBV (Financial Brand Value)</strong> — brand contribution to corporate earnings, calculated using the ISO 10668:2010 income approach.</li> <li><strong>SCV (Sustainability Compliance Value)</strong> — regulatory-risk-adjusted value integrating ISSB S1/S2, TNFD, EU CSRD, and Taiwan FSC phased ESG disclosure rules.</li> <li><strong>AIV (AI Visibility Value)</strong> — brand citation rate and position score across ChatGPT, Gemini, Perplexity, and Claude.</li></ul> <p>BCI addresses two structural blind spots of legacy valuation: (1) mandatory sustainability regulation has become a market-access determinant, and (2) generative AI platforms have become a primary brand-discovery channel (>30% consumer penetration as of 2025).</p> <p>Preliminary validation on 30 Taiwan-listed companies shows BCI explains 15–20% more subsequent revenue variation than single-dimension FBV alone, and detects brand capital impairment signals 1–2 quarters earlier.</p> <p>The methodology is published under CC BY-NC-SA 4.0, is designed to be globally applicable and regulation-neutral, and ships with a governance scaffold (weight calibration, audit trail, version control).</p>