According to the 2010 issue of Forbes Billionaires List, Lindner was worth an estimated $1.7 billion.

With his three sons, he controlled roughly 42% of American Financial Group, a holding company based in Cincinnati whose primary business is insurance and investments.

Lindner was a part-owner and chief executive officer of the Cincinnati Reds until he sold a majority interest to a group led by Robert Castellini on November 2, 2005, and stepped down as CEO.

His Great American Insurance Company was once the title sponsor of the Cincinnati Masters tennis tournament.

Although Lindner was a devout Baptist,[5] he was considered as one of the largest non-Jewish donors to the organized Jewish community in the United States.

In 2004, the Republican National Committee named Lindner as one of 62 "Super Rangers", the highest level of fundraising recognition, accorded to those who raise $300,000 or more.

Whereas the Lindner companies and financial institutions once operated on conservative, cautious principles they later became involved in riskier ventures.

He was survived by his wife, the former Edyth Bailey; his sons, Carl III, Craig and Keith; 12 grandchildren; and six great-grandchildren.