Law Firm AI Procurement Authority Has Shifted Upward — Decision Cycles 40–60% Longer at Mid-to-Large Firms

The Legal Stack's Legal AI Procurement Decision-Maker Shift Report 2026 (published August 10) documents that buy authorization for AI tools at mid-to-large firms has migrated from practice group chairs and enthusiast partners to CTO, CIO, or managing partner level — extending decision cycles by 40–60%. At small firms (under 50 lawyers), the managing partner or attorney-owner is the sole decision-maker in approximately 78% of AI purchases, and even those timelines extended from roughly 11 days in early 2024 to roughly 19 days by late 2025. For mid-sized firms navigating this shift, the implications cut both ways: internal AI decisions require more documentation, security attestation, and executive-level ROI framing than they did 18 months ago, but the same dynamic means that vendors trying to reach mid-sized firms must also adapt their sales motions. Firms that have already built formal AI governance processes are better positioned to evaluate and close vendor agreements quickly — a process advantage that compounds as the vendor market moves faster.