Background and Aim: The principle of independence with the special advantage that it has granted to commercial documents; He has provided the means for immediate payment regardless of the flaws in the basic contract in order to achieve some kind of certainty in business transactions. The purpose of the present research is to examine the defects of the warranty on demand in the American legal system.
Materials and Methods: This research is of theoretical type and the research method is descriptive-analytical and the method of data collection is library and has been done by referring to documents, books and articles.
Findings: In American law, banks are prohibited from issuing guarantees according to the instructions of the Federal Reserve, and issuing guarantees is left to financial and credit institutions and insurance companies.
Ethical Considerations: In order to organize this research, while observing the authenticity of the texts, honesty and fidelity have been observed.
Conclusion: American banks have started creating a new institution called guaranteed letters of credit. In this method, the principle of independence of the guaranteed letter of credit from the basic contract is specified.