As you are already aware, CNPC is the largest investor and partner in GNPOC.

CENTERFORSECURITYPOLICY: Center For Security Policy

In turn, CNPC is a Chinese government company and the largest shareholder (40%) in the Sudanese government's oil joint venture, the Greater Nile Petroleum Operating Company (GNPOC).

CENTERFORSECURITYPOLICY: Center For Security Policy

Additionally, a report issued last week by Africa Analysis, part of Financial Times Information, suggested that Talisman now is seeking to divest its stake in Sudan's GNPOC.

CENTERFORSECURITYPOLICY: Center For Security Policy

The oilfield in Unity is run by the Greater Nile Petroleum Operating Company (GNPOC), of which 5% is owned by Sudan's state Sudapec, 25% by Canada's Talisman Energy Co TLM.

BBC: Sudanese rebels