For case citations, texts and other lex mercatoria material on interpretation of intention of the parties:
http://tldb.uni-koeln.de/TLDB.html
Click TLDB's "List of Lex Mercatoria Principles".
No. IV.4.1 - Intentions of the parties
"The construction of a contract has to determine the common intention of the parties or, if no such intention can be determined, the meaning that reasonable persons of the same kind as the parties would give to it in the same circumstances, taking into account, in particular, the nature and purpose of the contract, the conduct of the parties and the meaning commonly given to contract terms and expressions in the trade concerned."
No. IV.4.2 - Interpretation in favour of effectiveness of contract
"Where there is doubt about the meaning of a contract term, an interpretation should be preferred that makes the contract lawful or effective ('ut res magis valeat quan pereat'; 'effet utile')."
No. IV.4.3 - Contra proferentem rule
"Where there is doubt about the meaning of a contract term that has not been individually negotiated, an interpretation against the party who supplied it should be preferred ('contra proferentem')."
No. IV.4.4. - Context-oriented interpretation
"Contractual stipulations shall be interpreted taking into account the whole contract in which they appear."
The TLDB database provides annotations to these texts. The TLDB annotations address Doctrine, Awards, Court Decisions, Principles/Model Laws, Conventions, National Legislation.
Pace Law School
Institute of International Commercial Law - Last updated January 28, 2003