The MBB Triad as Limit Case of Algorithmic Expropriation: Proprietary Agentic AI, Knowledge Capture, and the Failure of the Up-or-Out Contract

Abstract The premium strategy consulting industry — represented by McKinsey, Boston Consulting Group, and Bain at Boston Consulting Group, sustained workforce expansion concurs with progressively skewed functional composition toward AI/digital profiles; at Bain, the magnitude of the asymmetry across 2018–2025 is subject to structural uncertainty over the FY2018 base figure that the paper articulates with methodological transparency, while the direction of the phenomenon is convergent with the two prior firms. Second, the three firms display three distinct displacement regimes — public forced layoffs at McKinsey, AI-tilted continuous growth at BCG (33,500 employees, twenty-two consecutive years of revenue growth), and hybrid hidden-plus-voluntary mechanisms at Bain — yet all converge in the same structural outcome: intellectual capital crystallisation in proprietary Agentic AI assets, accompanied by explicit doctrinal articulation of the displacement logic (“do I need armies of analysts making PowerPoints? No” — Kate Smaje, McKinsey, 2025) and of the redistributive intent (“preserve the compensation pool for partners” — declared objective of Project Magnolia, as reported by Bloomberg). Third, the MBB triad operates a reflexive propagation of the extractive paradigm: the firms that have built proprietary Agentic AI systems on a century of uncompensated intellectual capital transfer are simultaneously the principal vendors of that methodology to the broader corporate world. We argue that the MBB case constitutes the limit case of algorithmic expropriation: even within organisations where ownership and labour are vertically integrated at the partner level, the residual cohort of sub-partner knowledge workers experiences the full force of intellectual capital appropriation, demonstrating that internal Coasian arrangements between firm and worker cannot resolve the externality. The implications for contractual reform of knowledge work — particularly through tokenisation mechanisms preserving residual rights over transferred intellectual capital, formalised in the companion theoretical paper — are discussed in light of the MBB evidence.