The data centre assets of failed investment bank Lehman Brothers have proved to be the most valuable part of the company, based on Barclays' purchase plan.

Barclays bought the business assets of the investment bank yesterday for just $250m, but then spent another $1.45bn on Lehman's two data centres and its corporate headquarters.

Barclays president Robert E. Diamond Jr said: "This is a once in a lifetime opportunity for Barclays. We welcome the opportunity to add Lehman's people and capabilities to the Barclays team."

The data centres cover 140,000 square feet in a 40-story tower in Jersey City, New Jersey. They were relocated there after the 11 September attacks to boost the security of the company's data processing capabilities.

The high valuation of the data centres is similar to JPMorgan's purchase of the assets of Bear Stearns, when much of the £270m asset price was based on the company's data centres in Brooklyn.