Article 13 CISG and its counterpart in Article 1:301(6) PECL both provide definitions of similar, albeit not identical terms: Article 13 CISG deals with the term “writing,”whereas Article 1:301(6) PECL addresses “written” statements.
The systematic position of the two provisions in the respective texts makes clear that both are only concerned with formal aspects of the terms “writing” and “written.” Article 13 CISG and Article 1:301(6) PECL neither expressly nor implicitly deal with other questions of interpretation of declarations, statements, and communications by the parties (these are subject to Article 8 CISG and Articles 5:101 PECL et seq.), nor do they address the question whether a written declaration was or must have been comprehensible to the recipient (which is to be resolved according to Articles 8 and 24 CISG).
REQUIREMENT OF A “WRITING” OR “WRITTEN” STATEMENTS IN THE CISG AND THE PECL
Both Article 1:301(6) PECL and Article 13 CISG limit the relevance of their definitions to writing requirements derived from the respective sets of rules (“[i]n these Principles” and “[f]or the purposes of this Convention”).
Within the PECL, the provisions containing such requirements can be divided into two groups: the first group consists of provisions that require a written statement to be applicable (Article 1:304(1) defining the moment when a period of time set by a party in a written statement begins to run, Article 2:207(2) addressing late acceptances contained in a writing, Article 2:210 governing professionals' written confirmations, and Article 3:208 regulating the effect of the principal's silence to a third party's written confirmation, including a request to ratify an act of the agent), whereas the provisions of the second group govern cases in which the contracting parties have provided for a writing requirement in their contract (Article 2.105(1) applying to “merger clauses”