Global investors are lining-up to acquire a 33% stake in Britain's biggest ports operator, Associated British Ports Holdings Ltd (ABP).

Goldman Sachs Infrastructure Partners and Prudential's infrastructure arm, Infracapital have put their 23% stake and 10% stake respectively for sale. The current shareholder structure of ABP is the following:

• Borealis Infrastructure, the infrastructure arm of Canada's pension fund Ontario Municipal Employees Retirement System (33 %);
• Singapore sovereign wealth fund GIC (33%);
• Goldman Sachs Infrastructure Partners (23 %); and
• Prudential's infrastructure arm, Infracapital (10 %).

According to sources, GIC and Borealis have the first right of refusal if other shareholders sell and they are believed to have settled on acquiring about another 7% each, giving them a 40 % stake each. This would leave a 19 % stake up for grabs for other potential investors.

A team composed by Abu Dhabi Investment Authority and 3i infrastructure, Canada Pension Plan Investment Board and the Universities Superannuation Scheme are among the investors interested in the ports operator.

According to sources, the first round of bids was carried out this week.

ABP was taken private in 2006 for £2.8 billion by the consortium mentioned above. At that moment, ABP was de-listed from the London Stock Exchange.

In 2013 ABP had revenue of £503.8 million (+6.8 % compared to 2012) and an underlying operating profit of £250 million (+8.8 % compared to 2012). Traffic figures also grew at around 4 % during 2013.