diff --git a/CHANGELOG.md b/CHANGELOG.md
index bb31924..e93c2f1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,21 @@
 
 All notable changes to `@sharp-api/client` are documented here.
 
+## 0.4.0 — 2026-05-31
+
+### Added
+
+- `NormalizedOdds.is_active` (boolean). `false` indicates the market is
+  suspended/closed with the price frozen — mirrors OpticOdds `locked-odds` but
+  as a queryable field. Absent on the wire is treated as `true`.
+- `'odds:locked'` `WebSocketEventType` — supplementary stream event carrying the
+  suspended subset of a delta (1:1 with OpticOdds `locked-odds`). The rows also
+  arrive in the normal odds update with `is_active: false`.
+
+### Backward compatibility
+
+- Additive optional field; existing code is unaffected.
+
 ## 0.3.2 — 2026-05-07
 
 ### Changed
diff --git a/package.json b/package.json
index 83cca69..dd6a09b 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sharp-api/client",
-  "version": "0.3.2",
+  "version": "0.4.0",
   "description": "Official TypeScript/JavaScript client for the SharpAPI real-time sports betting odds API",
   "type": "module",
   "main": "./dist/index.cjs",
diff --git a/src/index.ts b/src/index.ts
index 56a8e2c..8e09634 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -306,6 +306,13 @@ export interface NormalizedOdds extends NestedRefs {
   eventStartTime: string
   timestamp: string
   isLive: boolean
+  /**
+   * `true` (default) = market open and bettable; `false` = market
+   * suspended/closed with the price frozen (mirrors OpticOdds `locked-odds`).
+   * Absent on the wire is treated as `true`. Wire key is snake_case
+   * `is_active` (the client returns raw JSON without key transforms). SHA-3803.
+   */
+  is_active: boolean
   status: 'upcoming' | 'live' | 'ended'
 }
 
@@ -990,6 +997,7 @@ export type WebSocketEventType =
   | 'initial'
   | 'snapshot_complete'
   | 'odds_update'
+  | 'odds:locked'
   | 'ev:detected'
   | 'ev:expired'
   | 'arb:detected'