In 1999 Merrill Lynch Capital Markets expanded its lease to .Staff. "In Brief." Houston Chronicle. Sunday March 21, 1999. Business 6. Retrieved on November 11, 2009. In 2000 Ernst & Young occupied of space on five floors in 1 Houston Center.Bivins, Ralph. "Office Tower Planned on Downtown Houston Tract." Knight Ridder/Tribune Business News. February 14, 2000. Retrieved on November 12, 2009. When 5 Houston Center opened in 2003, Ernst & Young pulled its operations from 1 Houston Center and moved them into 5 Houston Center, leaving of space in 1 Houston Center vacant. Two of the five floors that Ernst & Young left behind were leased to other firms by July 2003.Bivins, Ralph. "SURVIVAL OF THE NEWEST / OCCUPANCY DOWNTOWN TUMBLING, BUT THREE TOWERS DEFY TREND." Houston Chronicle. Sunday July 27, 2003. Business 1. Retrieved on November 11, 2009. Cozen O'Connor opened an office in 1 Houston Center in 2004."Cozen O'Connor Opens Houston Office." Insurance Journal. June 7, 2004. Retrieved on November 11, 2009. On November 22, 2005, Alain Robert, a French rock and urban climber nicknamed "Spider-Man", was arrested attempting to climb the building."French 'Spider-Man' Climbs 31-Story Tower." CRI English. Accessed August 3, 2008. In 2008 the law firm Fish & Richardson opened an office in 1 Houston Center on October 1, 2008.Gunter, Ford. "National law firms flock to Houston." Houston Business Journal. Friday October 24, 2008. Modified Monday October 27, 2008. Retrieved on November 11, 2009. As of 2010 Haynes and Boone has an office in 1 Houston Center."Houston." Haynes and Boone. Retrieved on January 18, 2010.
