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When the form is re-initialized from the submission documents, you must also supply the signatures. The initialization process will verify that the data has not changed (i.e., has not been tampered with) and the signature is still valid. If the signature is not valid, it is removed and the entire Section is displayed with a visible error (large red background). If it is valid, there is a green background and the Section cannot be edited.

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One way signatures become invalid is when the production form is changed to remove a control that was inside a signed section. See Admin Best Practices for updating a form/workflow in production.

Signed Sections

provides true digital signature functionality via a Section control in your form. The user signs a specific Section, so that different parts of the form can be signed by different people rather than a signature being applied only to the entire form. Signed sections provide authenticated digital signatures with either a Wet Signature or Text/Signature Image type of signature. 

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The Lock sign means that the next person in the workflow can not remove the signature and edit the signed data. A good use case is an employee performance review where the manager starts the form, and signs the review, and sends it to the employee. You would check Lock sign so the employee cannot unsign and edit the data entered by the manager.

The Must sign property makes the signature required. With Must sign, a form cannot be submitted or a workflow is not sent to the next person until the signature is added.Checking Must sign will disable the None Required option from the Signature dropdown and automatically selects Text/Signature Image. You can change the Signature dropdown to Wet Signature.  

Sections that are hidden/not hidden via a rule or the Visible property in the designer, behave as stated below with respect to Must Sign:

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