Altair makes software for engineering simulation, high-performance computing (HPC), and data analytics/AI, and is being acquired by Siemens Industry for $113 per share in cash. Altair's core product is its HyperWorks simulation platform, which lets engineers virtually test and optimize product designs across structural, fluid, thermal, electromagnetic, and other physics disciplines before building physical prototypes. Key simulation products include HyperMesh, OptiStruct, and SimSolid. Altair's HPC business, centered on its PBS Works suite, helps customers schedule and allocate compute workloads across on-premise and cloud environments. The data analytics and AI business, built around the RapidMiner platform, serves primarily banking, financial services, and insurance customers, offering machine learning, data preparation, and SAS language compatibility for legacy users. Altair's customers are primarily large manufacturers in automotive, aerospace, and heavy equipment, with a growing presence in semiconductors, BFSI, and life sciences. Altair pioneered a "units-based" licensing model, where customers buy a pool of flexible units applicable across the full software portfolio rather than purchasing per-seat licenses for individual products. This model lowers adoption barriers and drives cross-sell within accounts. About 92% of software revenue is recurring, and roughly 60% of new software revenue comes from expansion within existing customers. Altair also runs a smaller Client Engineering Services segment, placing technical specialists at customer sites, which deepens relationships but carries lower margins than software.