Aviva has increased its North American investor base to account for about a quarter of its shares as it capitalises on its higher profile across the Atlantic after buying AmerUs last year.
The current figure compares with about 15 per cent only 18 months ago, and Britain's biggest insurer sees further growth to come.
"There is a lot of money in the US that needs to be invested and it is increasingly being invested inglobal companies likeours," Philip Scott, Aviva's finance director, said. "We have increased our scale in the US a lot, and I wouldn't be surprised to see that [the increase] go a bit further."
Aviva announced the $2.9bn (£1.4bn) AmerUS acquisition in July 2006 and combined the company with its own US business in November. Mr Scott led the acquisition, which increased the size of Aviva's US operations fourfold.
The combined business is run by the former AmerUS chief executive, Tom Godlasky, from AmerUS's headquarters in Des Moines, Iowa. The business is branded as Aviva USA and recently announced a $150m plan to build new headquarters in Des Moines on a 71-acre site.
Aviva declined to give details of North American institutional investors that had bought or increased their stakes. But Bloomberg lists State Street Global Advisors, Alliance Bernstein, Franklin Templeton and Capital Research among the insurer's top 20 investors.
Aviva, which owns Norwich Union in the UK, will hold an investor day in New York on 17 October to showcase the US business and give an update on the group's progress under its new management team.
Andrew Moss took over as chief executive in July when Richard Harvey stepped down. Mr Scott took over Mr Moss's job as finance director after running the international long-term savings and general insurance businesses.Reuse content