The engagement letter is required to be signed by those that are deemed authorized representatives of the engaging party. For an audit firm, the engagement letter should be signed by one of the partners of the firm.
Purpose of Engagement Letters It's the responsibility of the service provider to draft this document in alignment with the services to be rendered and in compliance with legal and professional standards.
The internal auditor and the auditee should agree on the terms of the engagement before commencement. The agreed terms would need to be recorded in an engagement letter.
An engagement letter is drafted by the company rendering the service, often with the help of a lawyer. It is than presented to the client, and both parties must sign in order for it to be legally binding.
In summary, both the auditing firm and the organization being audited must sign the SOC report, with the organization signing the Management Assertion and Representation and the auditor signing the independent Auditors opinion within the SOC report.
An audit engagement is an agreement between a client and an independent third-party auditor to perform an audit of some element of the client's business, such as accounting records, financial statements, internal controls, regulatory compliance, information systems, operational processes, etc.
The Management Representation Letter is a letter addressed to a federal entity's external auditor, signed by senior management.