For years, buying legal AI meant buying seats—flat annual subscriptions that priced predictably regardless of use. That model is now under real strain. As AI platforms take on more autonomous work, the cost of running them has become far more variable, and vendors are beginning to price accordingly. At the same time, corporate clients are pushing in the opposite direction, asking for fixed fees and predictable spend on AI-assisted work. This piece traces the squeeze that opens up between those two shifts, why it is showing up in real invoices, and what firms can do about it.