diff --git a/methods/websocket/signatureUnsubscribe.md b/methods/websocket/signatureUnsubscribe.md
new file mode 100644
index 0000000..63d0cb3
--- /dev/null
+++ b/methods/websocket/signatureUnsubscribe.md
@@ -0,0 +1,7 @@
+# signatureUnsubscribe
+
+Cancels a subscription created by `signatureSubscribe` on the same WebSocket connection and returns `true`. An id that this connection does not hold returns `InvalidParams` (-32602) with the message `Invalid subscription id.`
+
+## Implementation notes
+
+[**Agave**](../../implementations/agave.md) implements this method in the [pinned PubSub trait](https://github.com/anza-xyz/agave/blob/6dd9d38771e46103b9680357a855804165612602/rpc/src/rpc_pubsub.rs#L148).
diff --git a/methods/websocket/signatureUnsubscribe.yaml b/methods/websocket/signatureUnsubscribe.yaml
new file mode 100644
index 0000000..d229a11
--- /dev/null
+++ b/methods/websocket/signatureUnsubscribe.yaml
@@ -0,0 +1,27 @@
+name: signatureUnsubscribe
+status: standard
+summary: Cancel a signatureSubscribe subscription.
+params:
+  - name: subscriptionId
+    required: true
+    summary: Identifier returned by signatureSubscribe on this connection.
+    schema: { $ref: '#/components/schemas/U64' }
+result:
+  name: success
+  summary: True when the subscription is cancelled.
+  schema: { type: boolean }
+errors:
+  - $ref: '#/components/errors/InvalidParams'
+examples:
+  - name: basic
+    summary: Cancel a subscription.
+    params:
+      - name: subscriptionId
+        value: 1
+    result:
+      name: success
+      value: true
+implementations:
+  agave: { status: full }
+  cloudbreak: { status: none }
+  superbank: { status: none }
diff --git a/proposals/0052-signature-unsubscribe.md b/proposals/0052-signature-unsubscribe.md
new file mode 100644
index 0000000..c52d61c
--- /dev/null
+++ b/proposals/0052-signature-unsubscribe.md
@@ -0,0 +1,38 @@
+---
+number: 0052
+title: Add signatureUnsubscribe
+authors: [rpcpool]
+status: draft
+created: 2026-09-14
+reference-implementations: [https://github.com/anza-xyz/agave/blob/6dd9d38771e46103b9680357a855804165612602/rpc/src/rpc_pubsub.rs#L148]
+---
+
+# Add signatureUnsubscribe
+
+## Summary
+
+Add the signatureUnsubscribe WebSocket RPC method.
+
+## Motivation
+
+Agave exposes this public PubSub lifecycle method.
+
+## Specification
+
+Add the paired WebSocket method page. It defines the connection-scoped cancellation request, true result, and invalid-subscription error.
+
+## Return-type impact
+
+The method returns true after cancellation.
+
+## Compatibility
+
+This is additive. Agave implements it. Cloudbreak and Superbank do not currently implement WebSocket PubSub.
+
+## Reference implementation
+
+[Agave pinned handler](https://github.com/anza-xyz/agave/blob/6dd9d38771e46103b9680357a855804165612602/rpc/src/rpc_pubsub.rs#L148)
+
+## Security considerations
+
+Servers release the subscription resources when this call succeeds.
diff --git a/spec-info.yaml b/spec-info.yaml
index 892ea85..bca4391 100644
--- a/spec-info.yaml
+++ b/spec-info.yaml
@@ -1,5 +1,5 @@
 title: Solana JSON-RPC API
-version: 0.1.0
+version: 0.2.0
 license:
   name: MIT
   url: https://opensource.org/license/mit/