CSBG (Customer Support Business Group) is Lam's recurring revenue segment, generating ~$3.1B in CY2025 from spares, services, upgrades, and reliant technology for an installed base of over 90,000 chambers worldwide. Record upgrade revenue grew 90%+ YoY in CY2025 as memory fabs convert from 128-layer to 256-layer NAND using existing equipment frames. CSBG is structurally higher-margin than equipment sales because it leverages the existing installed base. As Lam's equipment fleet grows, CSBG provides a growing annuity stream that reduces cyclicality. This segment is the most defensible part of Lam's business -- once a fab runs Lam etch tools, they depend on Lam for spares, upgrades, and process optimization.
CSBG upgrade revenue grew 90%+ YoY in CY2025, driven by technology conversions from 128-layer to 256-layer NAND using existing chamber frames
Lam's upgrade business allows existing chamber frames to be converted for new technology nodes -- for example, upgrading a 128-layer NAND etch chamber to handle 256-layer processes. This is significantly cheaper for customers than buying entirely new systems and generates high margins for Lam. Upgrade revenue hit a record in CY2025, growing 90%+ YoY, as the NAND technology transition created a wave of conversion demand. This business model also applies to logic (FinFET to GAA conversions) and DRAM (conventional to HBM-ready). The upgrade cycle is partially independent of the new equipment cycle, providing a buffer during downturns.
Record upgrade revenue in CY2025 grew 90%+ YoY, driven by NAND technology transitions from 128-layer to 256-layer