What is the independence principle?

The relationship of the buyer and the bank is separate and distinct from the relationship of the buyer and seller in the main contract; the bank is not  required to investigate if the contract underlying the LC has been fulfilled or not because in transactions involving LC, banks deal only with documents and not goods (BPI v. De Reny Fabric Industries, Inc., L-­‐2481, Oct. 16, 1970). In effect, the buyer has no course of action against the issuing bank.