diff --git a/app/databus/provider_chains.py b/app/databus/provider_chains.py
index 4ba997e..9ce2a53 100644
--- a/app/databus/provider_chains.py
+++ b/app/databus/provider_chains.py
@@ -1,8 +1,11 @@
-"""Backward-compat shim - moved to app.databus._generated.provider_chains in P3B.
+"""Backward-compat shim - moved to app.domains.databus._generated.provider_chains in P4.
+
+Phase 4 of AUDIT-2026-Q3.md moved app/databus/_generated/ to
+app/domains/databus/_generated/. This shim re-exports for legacy callers.
 
 This module is auto-generated. Do not edit manually.
 Regenerate via: scripts/generate_provider_chains.py
 """
-from app.databus._generated.provider_chains import (  # noqa: F401
+from app.domains.databus._generated.provider_chains import (  # noqa: F401
     build_provider_chains,
 )
diff --git a/app/databus/providers.py b/app/databus/providers.py
index a83e076..59fa387 100644
--- a/app/databus/providers.py
+++ b/app/databus/providers.py
@@ -1,6 +1,10 @@
-"""Backward-compat shim — moved to app.databus.providers package in P3B."""
-from app.databus.providers import *  # noqa: F401,F403
-from app.databus.providers import (  # noqa: F401
+"""Backward-compat shim — moved to app.domains.databus.providers in P4.
+
+Phase 4 of AUDIT-2026-Q3.md moved app/databus/providers/ to
+app/domains/databus/providers/. This shim re-exports the public
+surface for legacy callers.
+"""
+from app.domains.databus.providers import (  # noqa: F401
     Provider,
     ProviderChain,
     ProviderTier,
diff --git a/app/databus/_generated/__init__.py b/app/domains/databus/_generated/__init__.py
similarity index 100%
rename from app/databus/_generated/__init__.py
rename to app/domains/databus/_generated/__init__.py
diff --git a/app/databus/_generated/provider_chains.py b/app/domains/databus/_generated/provider_chains.py
similarity index 100%
rename from app/databus/_generated/provider_chains.py
rename to app/domains/databus/_generated/provider_chains.py
diff --git a/app/databus/providers/__init__.py b/app/domains/databus/providers/__init__.py
similarity index 100%
rename from app/databus/providers/__init__.py
rename to app/domains/databus/providers/__init__.py
diff --git a/app/databus/providers/btc.py b/app/domains/databus/providers/btc.py
similarity index 100%
rename from app/databus/providers/btc.py
rename to app/domains/databus/providers/btc.py
diff --git a/app/databus/providers/evm.py b/app/domains/databus/providers/evm.py
similarity index 100%
rename from app/databus/providers/evm.py
rename to app/domains/databus/providers/evm.py
diff --git a/app/databus/providers/free_tier.py b/app/domains/databus/providers/free_tier.py
similarity index 100%
rename from app/databus/providers/free_tier.py
rename to app/domains/databus/providers/free_tier.py
diff --git a/app/databus/providers/mcp_servers.py b/app/domains/databus/providers/mcp_servers.py
similarity index 100%
rename from app/databus/providers/mcp_servers.py
rename to app/domains/databus/providers/mcp_servers.py
diff --git a/app/databus/providers/paid_tier.py b/app/domains/databus/providers/paid_tier.py
similarity index 100%
rename from app/databus/providers/paid_tier.py
rename to app/domains/databus/providers/paid_tier.py
diff --git a/app/databus/providers/solana.py b/app/domains/databus/providers/solana.py
similarity index 100%
rename from app/databus/providers/solana.py
rename to app/domains/databus/providers/solana.py