diff --git a/specs/src/consensus.md b/specs/src/consensus.md
index 69dc17f136..fa708ce95d 100644
--- a/specs/src/consensus.md
+++ b/specs/src/consensus.md
@@ -32,6 +32,7 @@
| `SHARE_INFO_BYTES` | `uint64` | `1` | `byte` | The number of bytes used for [share](data_structures.md#share) information |
| `SHARE_RESERVED_BYTES` | `uint64` | `4` | `byte` | The number of bytes used to store the index of the first transaction in a transaction share. Must be able to represent any integer up to and including `SHARE_SIZE - 1`. |
| `SHARE_SIZE` | `uint64` | `512` | `byte` | Size of transaction and blob [shares](data_structures.md#share), in bytes. |
+| `SignerSize` | `int` | `20` | `byte` | The number of bytes used to store the signer in a [share](data_structures.md#share). |
| `STATE_SUBTREE_RESERVED_BYTES` | `uint64` | `1` | `byte` | Number of bytes reserved to identify state subtrees. |
| `UNBONDING_DURATION` | `uint32` | | `block` | Duration, in blocks, for unbonding a validator or delegation. |
| `v1.Version` | `uint64` | `1` | | First version of the application. Breaking changes (hard forks) must update this parameter. |
diff --git a/specs/src/figures/first_share_with_signer.dot b/specs/src/figures/first_share_with_signer.dot
new file mode 100644
index 0000000000..d22e7eff1e
--- /dev/null
+++ b/specs/src/figures/first_share_with_signer.dot
@@ -0,0 +1,25 @@
+digraph G {
+ node [shape = record, penwidth = 0];
+
+ share [label=<
+
+
+
0
+
1
+
29
+
30
+
34
+
54
+
512
+
+
+
namespace version
+
namespace id
+
info byte
+
sequence length
+
signer
+
blob1
+
+
+ >];
+}
diff --git a/specs/src/figures/first_share_with_signer.svg b/specs/src/figures/first_share_with_signer.svg
new file mode 100644
index 0000000000..71dfe3d8e3
--- /dev/null
+++ b/specs/src/figures/first_share_with_signer.svg
@@ -0,0 +1,31 @@
+
+
\ No newline at end of file
diff --git a/specs/src/shares.md b/specs/src/shares.md
index ce84a8950a..59ed91c9f3 100644
--- a/specs/src/shares.md
+++ b/specs/src/shares.md
@@ -23,6 +23,12 @@ User submitted transactions are split into shares (see [share splitting](#share-
## Share Format
+### Share Version
+
+The share version is a 7-bit big-endian unsigned integer that is used to indicate the version of the [share format](#share-format). A new share version MUST be introduced if the share format changes in a way that is not backwards compatible. There are two share versions [share version 0](#share-version-0) and [share version 1](#share-version-1).
+
+### Share Version 0
+
Every share has a fixed size [`SHARE_SIZE`](./consensus.md#constants). The share format below is consistent for all shares:
- The first [`NAMESPACE_VERSION_SIZE`](./consensus.md#constants) bytes of a share's raw data is the namespace version of that share (denoted by "namespace version" in the figure below).
@@ -44,9 +50,17 @@ Continuation share in a sequence:
Since raw data that exceeds [`SHARE_SIZE`](./consensus.md#constants)`-`[`NAMESPACE_SIZE`](./consensus.md#constants)`-`[`SHARE_INFO_BYTES`](./consensus.md#constants) `-` [`SEQUENCE_BYTES`](./consensus.md#constants) bytes will span more than one share, developers MAY choose to encode additional metadata in their raw blob data prior to inclusion in a Celestia block. For example, Celestia transaction shares encode additional metadata in the form of "reserved bytes".
-### Share Version
+### Share Version 1
+
+Share version 1 is similar to share version 0 with the addition of a `signer` field. The signer is located after the sequence length in the first share. The signer is [`SIGNER_SIZE`](./consensus.md#constants) bytes.
+
+First share in a sequence with signer:
+
+
+
+Continuation share in a sequence:
-The share version is a 7-bit big-endian unsigned integer that is used to indicate the version of the [share format](#share-format). The only supported share version is `0`. A new share version MUST be introduced if the share format changes in a way that is not backwards compatible.
+
## Transaction Shares