Trinity College has sold the long-term lease of the O2 Arena to pensions insurance firm Rothesay for £90 million, following a “competitive auction process”.

The deal, signed last week, now gives Rothesay a 999-year lease on one of London’s most popular entertainment venues, known for its sporting, musical, and theatrical events.

This comes after Trinity decided to put up its lease for auction in November. It is unclear what prompted Cambridge’s wealthiest College to sell.

Rothesay, the new owner of the lease, is Britain’s largest pensions insurance specialist and the title sponsor of England’s home Test cricket matches.

In a joint statement to Sky News, Rothesay and Trinity said they were “pleased to confirm that Rothesay will be the long-term owner of The O2 Arena, following a competitive auction process for the lease of this London landmark”.

A Rothesay spokesperson added: “Prestigious and high-quality property assets like the O2 form an important part of Rothesay’s investment strategy, providing the predictable and dependable returns which create real security for the one million-plus pensions we protect.”

In 2009, the College added the O2 Arena to its long list of assets, paying £24m to the property companies Lend Lease and Quintain.

These property companies acquired the Millennium Dome, as it was known at the time, for free in 2002, after its unsuccessful launch as an exhibition centre two years earlier.

The venue then opened in its current form in 2007 and is currently operated by Anschutz Entertainment Group (AEG).