diff --git a/packages/safe-chain/src/registryProxy/registryProxy.environment-variables.spec.js b/packages/safe-chain/src/registryProxy/registryProxy.environment-variables.spec.js
new file mode 100644
index 00000000..cd8329c9
--- /dev/null
+++ b/packages/safe-chain/src/registryProxy/registryProxy.environment-variables.spec.js
@@ -0,0 +1,13 @@
+import { describe, it } from "node:test";
+import assert from "node:assert";
+import { mergeSafeChainProxyEnvironmentVariables } from "./registryProxy.js";
+
+describe("registryProxy.environmentVariables", () => {
+  it("should copy environment variables with empty string values", () => {
+    const envVars = mergeSafeChainProxyEnvironmentVariables({
+      EMPTY_VAR: "",
+    });
+
+    assert.strictEqual(envVars.EMPTY_VAR, "");
+  });
+});
diff --git a/packages/safe-chain/src/registryProxy/registryProxy.js b/packages/safe-chain/src/registryProxy/registryProxy.js
index 0b009bbd..509db28f 100644
--- a/packages/safe-chain/src/registryProxy/registryProxy.js
+++ b/packages/safe-chain/src/registryProxy/registryProxy.js
@@ -66,7 +66,7 @@ export function mergeSafeChainProxyEnvironmentVariables(env) {
     // So we only copy the variable if it's not already set in a different case
     const upperKey = key.toUpperCase();
 
-    if (!proxyEnv[upperKey] && env[key]) {
+    if (!(upperKey in proxyEnv) && env[key] !== undefined) {
       proxyEnv[key] = env[key];
     }
   }