In Q3'26, LRCX's total operating expenses reached $863.5M USD, comprising $583.2M USD in R&D expenses and $280.3M USD in SG&A expenses, marking a slight quarterly increase from $843.8M USD in Q2'26 and reflecting ongoing investment in research amid stable administrative costs. Over the period from Q4'23 to Q3'26, operating expenses exhibited a steady upward trend, growing from $601.8M USD to $863.5M USD, driven primarily by R&D expenses which surged 45% from $402M USD to $583.2M USD, while SG&A expenses rose more modestly by 40% from $199.8M USD to $280.3M USD; notable acceleration occurred post-Q3'24, with R&D peaking at $580.2M USD in Q4'25 before stabilizing, underscoring a focus on innovation in a volatile semiconductor sector. R&D consistently dominated the breakdown, accounting for 65-68% of total expenses throughout, highlighting its role as the primary cost driver in LRCX's operations.