==== EIP 191: Signed Data Standard  (DRAFT) ====
[[dido:public:ra:xapend:xapend.b_stds:defact:ethereum:eip| Return to Ethereum ERCs ]]

  : **Note**: The following is an excerpt from the official Ethereum site. It is provided here as a convenience and is not authoritative. Refer to the original document as the authoritative reference.

<table>
<caption>Data sheet for Signed Data Standard</caption>
| Title                      | Signed Data Standard |
| Author                     | Martin Holst Swende, Nick Johnson |
| Status                     | Draft |
| Created                    | 2016-01-20  |
| Description                | [[http://eips.ethereum.org/EIPS/eip-191]] |
| Specification              | [[http://eips.ethereum.org/EIPS/eip-191#Specification]] |
| Category                   | ERC |
</table>

=== Abstract === 
This ERC proposes a specification about how to handle signed data in Ethereum contracts.

=== Motivation === 
//Several multisignature wallet implementations have been created which accepts presigned transactions. A presigned transaction is a chunk of binary signed_data, along with signature (r, s and v). The interpretation of the signed_data has not been specified, leading to several problems://

    * //Standard Ethereum transactions can be submitted as signed_data. An Ethereum transaction can be unpacked, into the following components: RLP<nonce, gasPrice, startGas, to, value, data> (hereby called RLPdata), r, s and v. If there are no syntactical constraints on signed_data, this means that RLPdata can be used as a syntactically valid presigned transaction.//
   * //Multisignature wallets have also had the problem that a presigned transaction has not been tied to a particular validator, i.e a specific [[dido:public:ra:xapend:xapend.a_glossary:w:wallet|wallet]]. Example:// \\ 
        //1. Users A, B and C have the 2/3-wallet X// \\ 
        //2. Users A, B and D have the 2/3-wallet Y// \\ 
        //3. User A and B submites presigned transaction to X.// \\ 
        //4. Attacker can now reuse their presigned transactions to X, and submit to Y.//