BNP Paribas Real Estate has a apparently been instructed to sell City Gate House in London.
Bloomberg has put the office building up for sale for around £100m.
City Gate House is 178,000 sq ft and is located at 39-45 Finsbury Square in London EC2.
The building is probably being sold as a likely refurbishment opportunity.
Bloomberg bought City Gate House for its own occupation from Tishman Speyer in 2000.
BNP Paribas Real Estate declined to comment.