One Shell Square, Louisiana’s tallest building, has been sold for an undisclosed amount to Hertz Investment Group, the Santa Monica, California, company announced Monday.

The purchase expands the already sizable local holdings for Hertz, which focuses on acquiring property in midsize cities such as Memphis, Tennessee, and St. Louis, Missouri. With the addition of One Shell Square at 701 Poydras St., Hertz now owns more than one-third of the Class A office buildings in New Orleans.

Hertz was founded by Judah Hertz, who also serves as the company’s chairman.

One Shell Square is one of six Class A office buildings in four Southeastern states that Hertz acquired from Equity Commonwealth, a real estate investment trust that decided to pull out of the region.

The company also purchased the Wells Fargo Tower, 20th Place and Inverness Central in Birmingham, Alabama; the Meridian tower in Columbia, South Carolina; and 300 N. Greene St. in Greensboro, North Carolina.

The sale marks Hertz’s entry into those cities.

The $415.5 million acquisition is the largest in Hertz’s history, the company said in a news release. Hertz has long practiced an investment strategy of buying buildings in areas where new construction is unlikely.

“Hertz Investment Group views these new markets as outstanding and extraordinary opportunities,” Hertz President Gary Horowitz said in a statement. “One of our primary strategies is to find outstanding office buildings in the central business districts of midsized cities. To acquire four in one deal is extremely rare and exciting for us.”

One Shell Square, a limestone and glass skyscraper designed by Skidmore, Owings and Merrill, was completed in 1972. The building, used mostly as office space, is 93.5 percent leased and counts Shell Oil and the Adams and Reese law firm among its tenants. The 51-story office tower contains more than 1.2 million square feet of space.

At 697 feet, the building is the tallest in the state and also is taller than Louisiana’s tallest peak, Driskill Mountain.

Hertz owns five other buildings in New Orleans: the Energy Centre, Poydras Center, the First Bank and Trust Tower, 400 Poydras and Westpark Office Building in Algiers. The company also owns a nine-level parking garage on Tchoupitoulas Street.

Hertz once owned what is now Benson Tower, but it sold the 400,000-square-foot building to family members of Saints and Pelicans owner Tom Benson for $42.1 million in 2009.

The sale of the building and an adjacent shopping mall and parking garage were key components of the long-term deal between the state and the Saints that will keep the team in New Orleans through 2025. It also laid the groundwork for the creation of Champions Square, the outdoor festival space next to the Mercedes-Benz Superdome.