Article L211-20 of the French Monetary and Financial Code
I. – The pledge of a securities account is constituted, both between the parties and in relation to the issuing legal entity and third parties, by a declaration signed by the account holder. This declaration shall include the particulars laid down by decree. The financial securities initially included in the pledged account, those substituted for them or added to them as security for the pledgee’s initial claim, in any manner…