The accelerating loss of global biodiversity signals an unfolding sixth mass extinction, posing profound threats to ecological systems, economic stability, and corporate resilience. In response, policy instruments such as Ecological Accounting, Biodiversity Net Gain (BNG), Nature-based Solutions (NbS), and the Taskforce on Nature-related Financial Disclosures (TNFD) have emerged to integrate ecological value into business strategy and financial governance. Marketed as win-win interventions, these frameworks promise carbon sequestration, resilience building, and biodiversity protection. Yet, as governments and corporations scale implementation, biodiversity is often treated as a secondary concern—or an afterthought. This article critically examines the intersection of biodiversity loss, ecosystem collapse, and corporate accountability, evaluating how BNG, NbS, and TNFD are reshaping environmental governance in the private sector. It assesses their potential to internalize ecological externalities, identifies key implementation risks, and outlines the structural changes required for systemic transformation. By linking planetary boundaries to boardroom decisions, the article underscores the urgent need for robust, enforceable biodiversity accounting mechanisms to mitigate ecosystem degradation and ensure long-term business viability.