Alliant Energy Corporation (NASDAQ: LNT), commonly known as Alliant Energy, is a public utility holding company headquartered in Madison, Wisconsin. Founded in 1917, the company's current structure emerged from a merger in 1998. As an S&P 500 component, Alliant Energy had approximately 2,948 employees in 2025 and reported a trailing twelve-month revenue of $4.418 billion as of March 31, 2026. Its market capitalization was around $18.7 billion as of May 2026.
Alliant Energy primarily provides regulated electric and natural gas services to retail customers in Iowa and Wisconsin through its utility subsidiaries, Interstate Power and Light Company (IPL) and Wisconsin Power and Light Company (WPL). The company is involved in the generation, distribution, and transmission of electricity, and the distribution and transportation of natural gas. Alliant Energy also invests in renewable energy sources, including significant wind and solar generating capacity.
In terms of patent litigation, Alliant Energy Corporation appears to operate as a defendant operating company. The company has been involved in one tracked case as a defendant and zero as a plaintiff. This posture indicates that Alliant Energy primarily defends against patent suits rather than asserting patent rights.
The single tracked case involving Alliant Energy is Midwest Energy Emissions Corp. et al. v. Berkshire Hathaway Energy Company et al., filed in July 2024, where Alliant Energy is listed as a defendant. The case is being litigated in the Southern District of Iowa.