Altair Engineering

Overview

Altair Engineering was an engineering software company founded in 1985 by James Scapa and headquartered in Troy, Michigan, best known for simulation, optimization and high-performance computing (HPC) software built on technology spun out of NASA (TechCrunch). It spent 32 years as a private company before a celebrated 2017 IPO, then sold itself to Siemens in a $10.6 billion deal announced in October 2024 and completed on March 26, 2025 — ending its run as an independent company (Reuters; HPCwire).

Thirty-two years private, then a blockbuster IPO

Altair’s story was unusual for a software company of its era: it was never venture-backed. Scapa, founder and CEO, told TechCrunch the company had once taken private-equity funding from General Atlantic, which he bought out in 2013, and used IPO proceeds to pay down debt (TechCrunch). Its software — simulation and optimization tools leveraging high-performance computing — counted Blue Origin, SpaceX and Facebook among its customers; Scapa joked it was “the coolest company you’ve never heard of,” competing against Dassault Systèmes, Siemens, Ansys and MSC Software (TechCrunch).

When Altair went public on November 1, 2017, the market loved it. The base offering priced at $13 per share raised $156 million; when underwriters fully exercised their option for another 1.8 million shares, the total sale reached $179.4 million (TechCrunch; MITechNews). Shares opened trading Thursday at $17, 31 percent above the offer price, rallied further to close Friday at $19.37, and closed the following Monday at $18.97 (MITechNews). TechCrunch, reporting on debut day, recorded shares soaring more than 40 percent to close at $18.31 (TechCrunch). Scapa himself sold more than 1.7 million shares in the offering, worth nearly $21 million (MITechNews).

By the IPO, Altair was already substantial: more than 2,000 employees in 68 offices across 24 countries, serving about 5,000 corporate clients, with product-design and LED-lighting subsidiaries alongside the software business (MITechNews). The company had $313.2 million in prior-year revenue and was profitable, with $10.2 million in net income — a rarity among software debutants of the period (TechCrunch). The stated use of proceeds was debt paydown, though the company said it was open to further acquisitions (MITechNews). By the time Siemens came calling, Altair employed more than 3,500 people and served thousands of customers across manufacturing, life sciences, energy and financial services (New Electronics).

The Siemens acquisition

Reuters reported on October 22, 2024 that Altair was exploring a sale; eight days later Siemens agreed to buy it for $10.6 billion at $113 per share, an 18.7 percent premium to the October 21 closing price (Reuters). The deal — fully cash-financed from Siemens’ existing resources — was the German industrial giant’s largest acquisition in years, aimed at expanding its digital business beyond its traditional trains-and-factory-equipment customers (Reuters; New Electronics).

Siemens framed the purchase as adding Altair’s capabilities in mechanical and electromagnetic simulation, HPC, data science and AI to its Siemens Xcelerator platform, creating what CEO Roland Busch called “the world’s most complete AI-powered design, engineering and simulation portfolio” and extending its “digital twin” offering (HPCwire). The transaction was expected to add about €600 million (roughly 8 percent) to Siemens’ digital business revenue and to become earnings-accretive about two years after closing (Reuters).

Closing came sooner than the expected second-half-of-2025 window: on March 26, 2025, Siemens announced it had completed the acquisition at an enterprise value of approximately $10 billion, folding Altair into its ONE Tech Company program (HPCwire; Industrial Equipment News). Scapa described the sale as “the culmination of nearly 40 years in which Altair has grown from a startup in Detroit to a world-class software and technology company” (New Electronics).

What this profile does not claim

• This profile does not present Altair as a currently operating independent company: the Siemens acquisition was completed on March 26, 2025, confirmed by independent trade press.
• Post-2017 revenue, headcount and product-line details were not verified from independent sources read; the profile states only the IPO-era figures and the 3,500+ employee figure from 2024 announcement coverage.
• The announced $10.6 billion equity value and the completed ~$10 billion enterprise value are given as reported; they are different figures, not an error.
• Whether the Altair brand survived inside Siemens was not verified from an independent source read and is not stated.
• The profile does not claim the acquisition was hostile; the $113-per-share price was an agreed offer (Reuters).