The headquarters building of magazine publisher Time Inc UK (formerly IPC Media) is to change hands in a £415 million deal announced this week.
Time Inc revealed its intention to sell the building in May this year.
The publishing firm will remain as a tenant of the office block which was completed in 2007 as part of the Bankside 123 development.
Oxford Properties, the global real estate arm of the Ontario Municipal Employees Retirement System, will acquire the building in a joint venture with Temasek.
"The Blue Fin Building is an iconic asset located in the heart of London's vibrant south bank district and is a great addition to Oxford's European portfolio, which now stands at over C$7 billion in assets under management in London and Paris," said Paul Brundage, executive vice president and senior managing director of Oxford Properties Europe.
"This transaction reinforces Oxford's belief that specific emerging 'live-work-play' destinations will outperform over time as a result of infrastructure improvements and shifting occupier dynamics.
"We are excited to enter into this transaction with Time Inc. and look forward to building a strong relationship with them in the years ahead as an important occupier and customer.
"This transaction represents the second joint venture in London with our partner Temasek as we look to build on our successful partnership at MidCity Place, London."
Time Inc executive vice president Jeff Bairstow commented: "We are very pleased with the outcome of this transaction.
"It's logical for us to monetise this valuable asset and place it in the hands of professional investors with proven track records.
"As part of the sale, we will lease back space at the Blue Fin Building and it will remain our UK headquarters.
"Since Time Inc became an independent US public company in 2014, Time Inc UK has invested in expanding its brands, content and audiences into new revenues streams, through a combination of organic investment and acquisition.
"These investments allow us to more effectively fulfil consumer passions with targeted content, products and services; as well as serve the advertisers who wish to reach them."
Two years ago M&G Real Estate bought the neighbouring Bankside 2 & 3 blocks for £315 million.