APCO's move comes more than 11 years after the firm underwent a management buyout backed by American merchant bank WindRiver.
In a statement for PRWeek, APCO said: "We have been talking to potential strategic partners or investors about replacing our current private equity investors who have been involved with APCO since our management buyout in 2004. We have had a wide range of discussions to date and we are considering all of our options to determine the best path forward for APCO's future and for our current investors and employee shareholders."
PRWeek understands that talks have taken place with Teneo, the acquisitive American consultancy, about a potential investment in the business. APCO declined to comment on these talks.
PRWeek also understands BlueFocus - the Chinese agency that has global expansion ambitions of its own, having bought a minority stake in Huntsworth - has also been in discussions with APCO. However, Teneo is thought to be leading the race for the consultancy.
It’s unclear whether a potential new investor would look to secure a minority stake in APCO by buying out WindRiver, or seek a greater or total share of the business, which is majority employee owned.
APCO, which is headquartered in Washington DC and has more than 30 offices worldwide, generated revenue of $118.1m (£79.3m) in 2014, according to PRWeek’s Global Agency Business Report, making it the world’s 18th largest PR network. Revenue was two per cent down on the previous year, however.
A swoop for APCO would be the biggest acquisition yet for Teneo, more than doubling its global headcount to over 1,100 with the addition of more than 600 APCO employees.
It would top a remarkable period of acquisitions for Teneo, which in July announced it had bought London-based PR firms Blue Rubicon and Stockwell, and later added Pendomer Communications.
Speaking to PRWeek after the Blue Rubicon and Stockwell acquisitions, Teneo International CEO Charles Watson said: "It’s our intention to grow a global business and what we saw [with the acquisitions] was the first big opening move in what we are currently about."
Teneo was founded in 2011 by Declan Kelly, the former US economic envoy to Northern Ireland, and Douglas Band, the top comms adviser for former US President Bill Clinton, as well as Paul Keary, a former senior MD of FTI Consulting.
Teneo declined to comment. PRWeek contacted BlueFocus for comment but received no reply at the time of publication.