Digitial Signature field Lost after document is scanned

[akhileshnirapure]

Hi

I have a simple document with below workflow

Note: the digital signature(s) are assigned and is associated with email address.

-------- document start

1st Signatory  :     {{FST_es_:signer1:digitalsignature}}

2nd Signatory : Manual Sign, then scan and upload.  Manualy sign here -->

3rd Signatory : {{THRD_es_:signer2:digitalsignature}}

-------- document end

--- Workflow ----

A (Digital) -->  B (Manual & Scan, Upload) --> C --> (Digital)

Note: 1st and 3rd uses local digitial signature based on certificate

1st Signatory  --> System uploads as new aggrement and assign person A for digital signature. Person A signs using digital signature (local one created in acrobat reader)

2nd Signatory --> Post 1st signatory the document is downloaded by person B from internal system and person B now signs the document manually (hand) and scans and upload to internal system. System uploads the document to Adobe Sign as new agreement

3rd Signatory --> Post 2nd Signatory, system uploads to adobe sign as new agreement and sets person c as signatory . person C digitally signs the document

--- Workflow ----

Approach

For above worklfow the system is interacting on 1:1 basis i.e. all the signatures are not sent from adobe sign service.. rather sent one-by-one, (its the requirement of system)

Issue

The Person A digital signature cannot be validated when it reaches to Person C (after manually sign and scan by person B)

Question:

1) Is this a valid approach?

2) if yes, then what step is missing?

3) can you recommend a better approach  to tackle this? (Note: we already tried the approach where all the signatures are done in AdobeSign service, this is not valid in our case)

4) any other flaw you can point out?

[margueritek]

A digital signature is a cryptographic validation that the PDF has not been modified. Part of that information is embedded in the PDF itself, so printing and scanning loses the information needed to validate the signature. Person B needs to sign the PDF in the PDF itself, and then forward the document to person C.

[akhileshnirapure]

thanks for response Margueriteck

Can you provide link to resource in documentation which confirm below?

A digital signature is a cryptographic validation that the PDF has not been modified. Part of that information is embedded in the PDF itself, so printing and scanning loses the information needed to validate the signature.

Also when you say

Person B needs to sign the PDF in the PDF itself, and then forward the document to person C

Are you saying Person B should be e-signing in PDF on AdobeSign portal?

[margueritek]

The AdobeSign service allows mixed digital signatures and eSignatures, so the workflow could be done with AdobeSign. Outside of AdobeSign, the non-digital signature could be a form field with a handwritten signature or a stamp.