Jolivet Investments has acquired No 1 Tithebarn in Liverpool city centre from administrator Grant Thornton.
The 115,000 sq ft building is the largest office investment to change hands in the city since 2011.
The quoting price was £5.35m, reflecting an initial yield of about 9%.
No 1 Tithebarn is situated in a prime location on the corner of Old Hall Street and Tithebarn Street at the centre of Liverpool's commercial core, immediately above Moorfields underground station.
The building was refurbished in 2010 and was previously owned by a joint venture between Legal & General and the collapsed Kenmore Property Group.
This refurbishment included most of the available office space which is specified to a 'Grade A' standard and is available in suites from 4,000 sq ft up to 50,000 sq ft.
Current occupiers include Morecrofts Solicitors, SDV, CSAV Group and Tata Consultancy Services.
Simon Storer, owner of Guernsey-based Jolivet Investments, said: "No 1 Tithebarn is a strategic acquisition for us and is the largest single asset in the portfolio, which is now valued at in excess of £75m.
"We intend to hold the building for the long-term and will therefore be relocating our management offices to the building so that we can ensure the building is working for our existing tenants and that we are doing our best to attract new occupiers."
Mark Worthington, director at CBRE who acted for Jolivet Investments, said: "We are delighted to have secured No 1 Tithebarn against stiff competition for the asset.
"I fully expect the building to out-perform the market as it will be able to offer high quality, functional space at a competitive cost managed at a local level which is an extremely strong proposition."
GVA represented the administrators.