The Articles of Agreement of the Asian Infrastructure Investment Bank (AIIB) were opened for signature on June 29, 2015. Fifty-seven countries participated in the negotiations of the Articles, with the final text adopted at the 5th Chief Negotiators' Meeting in Singapore on May 22, 2015. Representatives from the 57 Prospective Founding Members (PFMs) gathered on June 29, 2015 in Beijing at a Signing Ceremony of the Bank's Articles of Agreement at the Great Hall of the People and 50 PFMs signed the Articles. The list of countries that signed the Articles at the opening ceremony can be found here.
PFMs have until December 31, 2015 to sign the Articles, and until December 31, 2016 to complete domestic procedures for ratification, acceptance or approval of the Articles. When at least ten countries with subscriptions totaling at least 50% of AIIB's total capital allocation have completed these procedures, the Articles will enter into force under Article 59.
The text of the Articles can be found here.
During the negotiations of the Articles, the Chief Negotiators agreed that certain formulations in the text represented general understandings which needed to be recorded. The Chief Negotiators' Report, adopted at the same time as the final text of the Articles, summarizes these understandings, for future reference in interpreting the Articles.
The text of the Chief Negotiators' Report can be found here.
The Articles were negotiated in English. Article 34 specifies that the working language of the AIIB will be English, and that the Bank shall rely on the English text of the Articles for all decisions and for interpretations of the Articles.
The Articles were signed in English, Chinese and French texts, which are equally authentic. The Chinese text can be found here. The French text can be found here.
General information on the Articles and AIIB's operationalization can be found here.