DP World is asking the US to help it collect nearly $500m in final arbitration awards from Djibouti.
And the United Arab Emirates ports and logistics giant's Doraleh Container Terminal joint venture still has more outstanding, and possibly even larger, claims against the East African city-state.
The claims are part of the dispute over Djibouti's 2018 ouster of DP World in favour of China Merchants Port Holdings, a spin-off of China Merchants Group.
Battle in Washington
But for now, Doraleh is petitioning the US District Court in Washington DC, to confirm the awards it already holds from the London Court of International Arbitration against Djibouti. Confirmation would allow Doraleh to target Djibouti's assets in the US and, in particular, in its banks.
As a sovereign state, Djibouti has immunity from prosecution in US courts.
However, Doraleh's lawyers claim that Djibouti explicitly waived sovereign immunity by entering into the contract that governs the terminal concession.
Doraleh is a joint venture between state-controlled port company Port de Djibouti and DP World Djibouti FZCO, a subsidiary of the Dubai-based ports giant.
The awards it is seeking to enforce, which amount to some $486m plus interest, came this year in an arbitration that Djibouti had originally startedf in a bid to break a contract with DP World in favour of its new Chinese state-owned partner.
Djibouti and its lawyers had stopped participating in the arbitration before Doraleh's counterclaims were decided.
DP World originally took on management of Djibouti's port in 2000 soon after the country's President Ismail Omar Guelleh came to power. It won a concession in 2006 to develop a new container terminal for Djibouti under a 30-year exclusive contract, and Doraleh opened for business in December 2008.
However, in 2012 China Merchants Port began running the old terminal, an action that DP World alleged was in breach of its exclusive contractual rights.
Over a period of several years, Guelleh's government warmed to China Merchants Port and sought to push DP World out through arbitration.
Bribery allegations
The Chinese rival claimed that DP World had won its 2006 concession through bribing Guelleh's former ally Abdourahman Boreh. The London Court of International Arbitration panellists rejected this claim.
But in February 2018, DP World was ousted by presidential decree and China Merchants Port took control of operations at Doraleh.
The political and diplomatic aspect of the dispute is exacerbated by military activity at the port of Djibouti. China's People Liberation Army naval forces set up facilities there in 2017, near the US Navy's Camp Lemonnier.
Outside observers estimate the total claims in the complex and bitterly contested case run to more than $1bn.
For the time being, however, Doraleh is asking US courts to recognise the awards that it already has in hand. These cover mainly the exclusivity allegations plus arbitration costs, while further arbitration proceedings are still in the works for lost profits, management fees and Djibouti's termination of the venture.
DP World owns only 33.3% of the shares in the Doraleh joint venture. However, it has the right to appoint most of the board members and to make key decisions, thus allowing it to carry on the legal campaign against the ultimate owner of its majority partner.
DP World would presumably only receive a third of any proceeds from the dispute.
To complicate matters, China Merchants Port has a 23.5% share in the plaintiff's majority owner, Port de Djibouti.
Hong Kong proceedings
In addition to the London Court of International Arbitration and US federal court disputes against Djibouti, DP World won a Hong Kong court decision against China Merchants Port in December. This decision is under appeal.
Port de Djibouti chief executive Aboubaker Omar Hadi did not reply to a request for comment.