Parallel and Sequential authentication of digital signatures

[Satvik278465211v10]

When I send a document to a list of users for parallel signing, does each user add his cryptographic signature over the crypto-sign of the last user to sign the doc, or just on the bare document?

This may have several implications.

For example, 

A). A document may indicate agreement of all the undersigned to some body stated in it,

OR

B). A document may be needed to be signed by a group of people in a hierarchical organization, where each person only reviews the document if it has been signed by all those in the hierarchy below him / her.

I'm fairly confused as to how it currently works and couldn't find any supporting documentation.

[MikelKlink]

You mention digital / cryptographic signatures. Not all Acrobat Sign use cases actually collect digital / cryptographic signatures of the signers, they only collect non-cryptographic electronic ones and eventually create an Adobe cryptographic signature to secure the document. Are you sure you have a use case with cryptographic signer signatures?

The interoperable digital PDF signatures do not allow real parallel signatures, merely sequential ones. Non-cryptographic lectronic PDF signatures, on the other hand, can be implemented with real parallel signing.

[Meenakshi Negi]

Hi Satvik278465211v10,

Thank you for reaching out.

If you are looking for information on parallel and sequential signing workflow, please refer to the information provided on the following help page: https://helpx.adobe.com/sign/fedramp/user/sequential-workflow.html.

Check if that information answers your questions.

In the Parallel signing workflow, the recipients will sign to the signature field assigned to them anytime they open the form. They do not have to wait for others to sign it first. 

Let us know if you have any questions or are referring to something else.

Thanks,

Meenakshi

[Iacob34180015ig46]

Hi MeenakshiNegi

In case I use text tags in the document to specify signer field location (signer1, signer2 ...), and if I send the document for paralel signing, then will the recipients sign only in their field ? For example the first person in the list will sign signer1 field, the second person will sign signer2 field and so on ? 

[Abambo]

Yes.

[Satvik278465211v10]

Thanks for the reply, @MikelKlink and @Meenakshi Negi.

@Meenakshi Negi: I found the workflow you are referring to earlier. But it isn't what I am looking for. 

@MikelKlink: The use case I'd specify for parallel cryptographic signs is the difference between A (needs parallel signs) and B (sequential signs should do). More specifically in a parallel signing scheme, a signature should sign only the document's contents and not other signer's signatures.

Does this make sense?

[MikelKlink]

The use case I'd specify for parallel cryptographic signs is the difference between A (needs parallel signs) and B (sequential signs should do). More specifically in a parallel signing scheme, a signature should sign only the document's contents and not other signer's signatures.

Interoperable (as per specification) digital (cryptographic) PDF signatures do not allow true parallelism as each PDF revision can add only one signature (with a single SignerInfo) which has to cover all previous revisions.

For the old ISO 32000-1 interoperable signatures this has not been stated explicitly, merely implied. For the newer PAdES interoperable signatures it has been stated explicitly.

If you are looking into the flavor of Acrobat Sign signing processes that do not include per user cryptographic signature but only a single, finalizing cryptographic signature by Adobe Sign, parallelism is technically possible.