On July 12, 2010, Aon announced that it has agreed to buy Lincolnshire, Illinois, based Hewitt Associates for $ 4. 9 billion in cash and stock.

Aon has 29 offices throughout Australia, including every state and territory capital city.

Aon has sponsored the British Touring Car Championship team run by Arena Motorsport since 2009.

It has been benefited from steady economic growth and is now the second commercial and financial center of the city, housing international firms like Moody's, Citibank, Aon Corporation, Huawei, Millicom International Cellular, Nissan Motor Corporation represented by Taiyo Motors, Pan American Silver Corporation, a Sumitomo Corporation branch, Ernst & Young, and the " MegaCenter ", Bolivia's biggest shopping mall ( 52. 000 mts2 of construction ).

The development has succeeded in attracting tenants thus far, with one-third of the tower already pre-let to insurance broker Aon, which moved its headquarters to London from Chicago.

A former constituent of the FTSE 250 Index, the company has been a division of Aon Corporation since November 2008.

The evacuation of Aon's offices, ordered by Eric Eisenberg, was carried out quickly as 925 of the 1, 100 Aon employees present at the time managed to evacuate the building before United Airlines Flight 175 struck it twenty stories below them.

It also houses offices of Citizens Bank, Aberdeen Asset Management, Aon Corporation, The Boston Consulting Group, CrowdConnect Group, Goldman Sachs, and the law firm Ballard Spahr Andrews & Ingersoll, LLP.

In 1997 it bought The Minet Group, as well as insurance brokerage Alexander & Alexander Services, Inc. in a deal that made Aon ( temporarily ) the largest insurance broker worldwide.

Aon was created in 1982, when the Ryan Insurance Group ( founded by Pat Ryan in the 1960s ) merged with the Combined Insurance Company of America ( founded by W. Clement Stone in 1919 ).

The firm made no U. S. buys in 1998, but doubled its employee base with purchases including Spain's largest retail insurance broker, Gil y Carvajal, and the formation of Aon Korea, the first non-Korean firm of its kind to be licensed there.

Also that year Endurance Specialty, a Bermuda-based underwriting operation that Aon helped to establish in November 2001 along with other investors, went public.

In 2004 – 2005 Aon, along with other brokers including Marsh & McLennan and Willis, fell under regulatory investigation under New York Attorney General Eliot Spitzer and other state attorneys general.

The UK's Financial Services Authority stated that the fine related to the company's inadequate bribery and corruption controls, claiming that between January 14, 2005 and September 30, 2007 Aon had failed to properly assess the risks involved in its dealings with overseas firms and individuals.

Aon qualified for a 30 % discount on the fine as a result of its cooperation with the investigation.

On June 3, 2009, it was reported that Aon had signed a four year shirt sponsorship deal with English football giant Manchester United.

His other son Max Chilton races in the GP2 Series with backing from Aon.

Presently, the four tallest buildings in the city are Willis Tower ( formerly the Sears Tower, also a building with its own zip code ), Trump International Hotel and Tower, the Aon Center ( previously the Standard Oil Building ), and the John Hancock Center.

Combined later merged with the Patrick Ryan Group to form the Aon Corporation in 1987., and was sold to ACE Limited in April 2008 for $ 2. 56 billion.

The same white Carrara marble as that used on Aon Center is employed as an exterior cladding and interior finish for First Canadian Place, with approximate 45, 000 marble panels weighing around each.

Foreshadowing what would take place with First Canadian Place in 2007, one of the marble slabs of Aon Center, when it was named the Standard Oil Building, detached in 1974, falling and penetrating the roof of a neighbouring building, resulting in an eventual recladding of the entire Aon Center in white granite between 1992 and 1994.

In late 2009, it was announced that Brookfield Properties, the owners of First Canadian Place would follow the example of Aon Center and replace, over the course of three years, the tower's 45, 000 marble panels with new ones in glass ( not granite like Aon Center ), those on the main expanses with a white ceramic frit and the corners in a bronze tint.

The top five revenue generating firms were Mercer, Ernst & Young, Deloitte, Watson Wyatt ( now part of Towers Watson ), Aon ( now merged with Hewitt ), and PwC consulting.

The upper level carries local traffic to the Illinois Center, Aon Center and Prudential Plaza developments, and was built in conjunction with them ; it also takes traffic to the new Lakeshore Eastdevelopment.

The team's lead driver was Tom Chilton along with Alan Morrison also returning, running under the Team Aon banner ( Aon Corporation being their primary sponsor ).

Neal won two more races at Oulton Park and with team mate Shedden taking the other win, Honda Yuasa Racing Team became the first team to win all three races in a day since Team Aon won all three races at Silverstone in 2010.

Hewitt's operations were merged at that time with some elements of Aon's consulting arm to become a new subsidiary of the Aon Group called Aon Hewitt.

As a result, 175 employees of Aon were killed in the attacks, including Eisenberg and Kevin Cosgrove, a vice president of the company that made a call to 911 when the tower collapsed.

Aon plc is a British multinational corporation headquartered in London, United Kingdom, that provides risk management services, insurance and reinsurance brokerage, human capital and management consulting.

In January 2012, Aon announced that headquarters would be moved from Chicago to London.

Aon is the largest reinsurance broker in the world.

In 2011, Aon was ranked as the largest insurance broker in the world based on revenue.

, Aon is the principal sponsor of the Premier League team Manchester United.

In 1987, that company was renamed to Aon, a Gaelic word meaning oneness.

Aon is a global provider of insurance and reinsurance brokerage services, insurance products, risk and insurance advice, web-based risk management information systems, as well as other consulting services.

The brokerage unit Aon Risk Services provides retail property / casualty, liability, and other insurance products for groups and businesses, as well as risk management services.

Aon Re Global handles reinsurance brokerage services for aviation, marine, energy, professional liability, and other niche and specialty business lines.

Its consulting unit, Aon Consulting Worldwide, specializes in employee benefits administration.

Aon is the world's second largest insurance brokerage, and largest reinsurance brokerage.

He also trimmed staff and took other cost-cutting measures, and in 1987 he changed Combined's name to Aon.

Aon built a global presence through purchases.

Responding to industry demands, Aon announced its new fee disclosure policy in 1999, and the company reorganized to focus on buying personal line insurance firms and to integrate its acquisitions.

Despite its troubles, in 2000 Aon bought Reliance Group's accident and health insurance business, as well as Actuarial Sciences Associates, a compensation and employee benefits consulting company.

The next year Aon sold most of its holdings in Endurance.