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    CONSULTING × MODEL LAYERMay 2026· 9 min

    McKinsey + OpenAI (Lilli): When the Consulting Firm Owns the Memory, Not the Model

    McKinsey logoMcKinsey
    OpenAI logoOpenAI
    L1L2L6L8
    Verdict: L1 + L8 OVER L2

    Lilli Adoption

    Peak

    0 (Jun 2023)

    Now

    70%+ of firm weekly

    Compounding

    Layer Scoring

    L-1
    Resources
    L0
    Infra
    L1
    Data
    L2
    Models
    L3
    Gates
    L4
    Access
    L5
    Execution
    L6
    Orchestration
    L7
    Surface
    L8
    Memory
    L1 Data
    70 years of proprietary studies, expert memos, sector benchmarks. The moat that no model can reproduce.
    L2 Models
    Rented from OpenAI. Swappable in a weekend. McKinsey pays nothing to defend it.
    L3 Gates
    Client confidentiality, audit trails, citation back to source memos, table stakes for a consulting firm and a real barrier for AI-native competitors.
    L6 Orchestration
    Retrieval over the proprietary corpus, citation, expert routing, McKinsey-built orchestration on top of a rented model.
    L8 Memory
    Every engagement adds to Lilli. Compounding institutional memory, the second moat layer.

    Sublayer Impact Map

    Which of the 50 sublayers this case actually touches, and at what magnitude.

    L1 Data
    Data
    Client engagement archive
    plays here: McKinsey
    Owns
    Expert profiles & frameworks
    plays here: McKinsey
    Owns
    L2 Models
    Models
    Foundation model
    plays here: OpenAI (swappable)
    Share
    L3 Gates
    Gatekeeping
    Confidentiality + audit
    plays here: McKinsey-built
    Share
    L6 Orchestration
    Orchestration
    Corpus retrieval & routing
    plays here: McKinsey
    Owns
    L8 Memory
    Memory
    Institutional memory
    plays here: McKinsey
    Owns
    Per-engagement feedback
    plays here: McKinsey
    Share
    Impact: Touch = enters · Share = meaningful · Owns = dominates· bars = magnitude

    Intelligence Cube · 2D

    Footprint across Functions × Verticals × Layers, the three axes that determine structural fate.

    Layers × Verticals

    18 cells · 6×3

    L-1
    L0
    L1
    L2
    L3
    L4
    L5
    L6
    L7
    L8
    FinTech
    EdTech
    Legal
    Health
    Travel
    eCom
    Media
    Gov
    SaaS
    Horizontal

    Layers × Functions

    24 cells · 6×4

    L-1
    L0
    L1
    L2
    L3
    L4
    L5
    L6
    L7
    L8
    Dev/Eng
    Design
    Product
    PM/Proj
    Ops
    Mktg
    Sales
    CustCare
    Strategy
    Finance

    Two 2D projections of the Intelligence Cube (Functions × Verticals × Layers). Filled cells = this move occupies that intersection.

    Timeline

    Mid-2023

    Lilli launches internally, built on OpenAI, grounded in McKinsey's corpus.

    Late 2023

    Adoption ramps. Partners start citing Lilli output in client decks.

    Mid-2024

    70%+ of the firm uses Lilli weekly. Becomes standard tooling.

    2025

    Consulting firms emerge as some of the largest enterprise LLM customers, opposite of the predicted disruption.

    2026

    The model layer keeps commoditizing. McKinsey's L1+L8 advantage compounds. Pure-play AI strategy startups struggle to find buyers.

    - Who Wins

    • McKinsey, BCG, Bain. L1 (decades of proprietary client work) and L8 (compounding institutional memory), the two layers AI can't reproduce.
    • OpenAI / Anthropic. Consulting firms became some of their largest enterprise customers, not their competitors.
    • Any firm with deep proprietary archives. Law firms, accounting firms, hospitals, banks, the L1+L8 pattern generalizes.

    - Who Loses

    • Pure-play AI strategy startups. No L1, no L8, no client trust. The model is the cheapest layer to own, the others are the business.
    • Junior consulting headcount (slower growth). Drafting work compresses. The pyramid narrows. Entry-level path changes shape.
    • The 'AI will kill consulting' thesis. Falsified in real time. The opposite happened, consulting became one of the biggest beneficiaries.

    - Steelman: The Counter-Thesis

    The counter is that Lilli's moat is overstated because the *actual* output of consulting (the synthesized 60-page deck, the executive narrative, the client-relationship judgment) was always the value, not the underlying corpus. If frontier models continue to improve at long-form reasoning and synthesis, a well-prompted GPT-6 with public data may produce a McKinsey-grade strategy doc for a tenth the cost. McKinsey's corpus is large, but most of it is dated or sector-specific in ways that a generalist model can fluently approximate. The honest read: L1 protects them for 3–5 years; the open question is whether L8 (the compounding loop) can build a durable advantage before model capability closes the gap on the synthesis layer itself.

    The most misread AI story in professional services. Everyone asked "will ChatGPT kill McKinsey?" The structural answer was always no, and Lilli is the proof.

    The setup. In mid-2023 McKinsey shipped Lilli, an internal generative AI assistant built on OpenAI's models but grounded in McKinsey's own corpus: 100,000+ proprietary documents, 70 years of consulting studies, frameworks, interview notes, expert profiles. Within a year, the majority of the firm uses it weekly.

    The structural read:
    • L2 (model): rented from OpenAI. Commoditizing fast. McKinsey pays nothing to defend it.
    • L1 (proprietary data): 70 years of client work, expert memos, sector benchmarks. Cannot be reproduced by any model. This is the moat.
    • L6 (orchestration): retrieval over the corpus, citation, expert routing. McKinsey-built.
    • L8 (institutional memory): every engagement adds to Lilli. Compounding. Every consultant's output becomes future fuel.

    Law I, intelligence commoditizes downward. OpenAI's model is now interchangeable with Anthropic's or Google's at this task. McKinsey can swap the L2 underneath Lilli in a weekend. The L1 and L8 above it are untouched.

    Law III, value migrates to the scarcest layer. The scarce thing is not the ability to write a strategy memo. It's the 70 years of which strategies worked for which clients in which sector cycles. That data only exists inside McKinsey.

    The inverted lesson for everyone else. Most enterprises panicked about "AI displacing consulting." The opposite happened: consulting firms became some of the largest OpenAI/Anthropic customers, because they had the L1 and L8 to make the model valuable. The model layer is a tool. The data and memory layers are the business.

    What this means for your firm. If your competitive position is "we know things and we remember things," AI is an amplifier, not a threat, provided you own L1 and L8. If your position is "we can write good documents," the model now reproduces most of that work.

    Public reporting; figures approximate.

    What This Means for You

    Product Leader

    Map your product to the layers it actually owns vs. rents. The rented ones are where the counter-move work belongs.

    Investor

    Underwrite layer ownership, not feature count. The Cube footprint is the moat.

    Operator

    Audit your stack against Supply Chain of Intelligence. Anything sitting only at L7 is the layer to watch.

    AA

    Anand Arivukkarasu

    Ex-Meta product leader. Creator of Supply Chain of Intelligence™. Writes about where AI value accrues, and who can fire your product. LinkedIn

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    Worth sharing? Pull-quote: "L1 + L8 OVER L2"