Chime Communications is believed to be involved in talks with QBO about acquiring the full service PR agency.
Any deal would boost Chime's fee income to pounds 42,764,023, further consolidating its position as the largest player in the UK PR market.
Both Chime chairman Lord Bell and QBO MD Trevor Morris refused to comment on the speculation.
Bell has previously declared his intention to further consolidate Chime's number one position following the acquisition of Harvard PR and Insight PR for pounds 12 million and pounds 5 million respectively in March (PR Week, 24 March).
While the financial benefits of any deal will be a significant boost to Chime's market capitalisation, the strategic significance of purchasing QBO remains unclear.
'Normally when you make an acquisition it is a strategic fit to get into a particular area. With the acquisition of QBO it appears they are buying more of the same,' commented Jim Surguy, MD of marketing service advisor Results Business Consulting.
It is also unsure whether Chime's intentions are to merge QBO or leave it as a standalone agency potentially within The Good Relations Group.
One suggestion is that the acquisition is to boost Chime's consumer offering which at the moment consists of Green Moon which was rebranded as Bell Pottinger Public Relations in May (PR Week, 26 May).
Chime's interim results, published in September, showed pre-tax profits to be up 40 per cent to pounds 6.4 million.
QBO clients include Royal Mail, The Met Office, Norwich Union, British Gas and Telewest. Its offering includes internal communications, brand consultancy, promotions and sponsorship, design, and media training.