[Cryptography] Proposal of a fair contract signing protocol

[Adrian McCullagh]

Dear MK Shen,

I do not understand your terminology “against the law”.  If you mean criminally illegal then no it is not against the law ibut f you mean not legally enforceable under civil law then I see your protocol as being unnecessary and frankly overly complicated from a commercial perspective.

If Alice does to receive the acceptance communication (excluding the postal rule which I doubt would apply) even though Bob may have sent his acceptance there is no contract.  Further the Uniform Electronic Transactions Act (1999) deals with receipt of communications from a legal perspective (section 15).  My understanding is that this law has been enacted in more than 46 US States (though I have not recently checked).

In my law practice I advise my clients that if the acceptance is important then telephone the other side to satisfy themselves that the acceptance has been received.  Further take a diary note of the call and ask the otherside to send an acknowledgement.  Basically a three way handshake with an out of bounds communication.

If the acknowledgement is not received within a reasonable time then call again.  The whole exercise is to obtain as best as possible some evidence to support the acceptance being received by Alice.

Again, I do not see how your proposed protocol provides the evidence that a court will need.  Further, are we talking about minor contracts (less than $500) or contracts required by law to be in writing (statute of Frauds).

It is the value of implementing this that also needs to be taken into consideration.

Kind Regards

Dr. Adrian McCullagh
Ph.D. LL.B. (Hons) B.App. Sc. (Computing)

ODMOB Lawyers
Email: ajmccullagh57 at gmail.com
Email: amccullagh at live.com
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From: mok-kong shen
Sent: Saturday, 25 June 2016 9:31 AM
To: Adrian McCullagh; Salz, Rich; cryptography at metzdowd.com
Subject: Re: [Cryptography] Proposal of a fair contract signing protocol


You are entirely right that "Bob is under no legal obligation to do
anything with Alices Offer". The issue in the present thread assumes
however that Bob considers Alice's offer to be acceptable and does
step 2 and the protocol comes to an end with Alice doing step 3,
producing the contract document C and showing that it is signed by
both Alice and Bob. Now the question is whether the contract signing
process is fair. My argumentation is that it is indeed fair according
to the fairness definition I have given.

Is the matter now clear to you?

I don't fully understand your last paragraph: (1) If Alice and Bob
choose to do as desribed in my protocol, is that against the law??
(2) If you don't see any unfairness in what is done in the protocol,
then all the better for me, isn't it?

M. K. Shen

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