What is the name of Warren Buffett's primary investment company?

Warren Buffett’s primary investment company is Berkshire Hathaway.

Berkshire Hathaway is a diversified holding company that Buffett transformed from a struggling textile manufacturer into a major business empire. Buffett began buying shares in the 1960s and ultimately took control; by 1970, he was chairman. The company later shifted away from textiles and concentrated on insurance, investments, and ownership of operating businesses.

Berkshire is not simply a mutual fund or a personal brokerage account. It owns subsidiaries and holds large stakes in publicly traded companies. Its insurance operations, including GEICO and reinsurance businesses, have provided substantial capital for investments. Charlie Munger was a key partner in shaping the company’s approach.

“Buffett Partnership” is a common mix-up: that was the name of an earlier investment partnership Buffett operated from 1956 to 1969, before Berkshire became his central corporate vehicle.