diff --git a/tests/test_model_registry.py b/tests/test_model_registry.py
index 283b099107..76f462c5cf 100644
--- a/tests/test_model_registry.py
+++ b/tests/test_model_registry.py
@@ -1,5 +1,8 @@
 """Register each model set and check the registered ids exist on the HF Hub."""
 
+import os
+import subprocess
+import sys
 from dataclasses import dataclass
 
 import pytest
@@ -77,3 +80,85 @@ def test_quant_type():
     assert all(m.quant_type == QuantType.UNSLOTH for m in dynamic_quant_models)
     quant_tag = QUANT_TAG_MAP[QuantType.UNSLOTH]
     assert all(quant_tag in m.model_path for m in dynamic_quant_models)
+
+
+def _run_registry_child(body: str) -> subprocess.CompletedProcess:
+    """Run ``body`` in a fresh interpreter that first imports this directory's
+    ``conftest`` so it inherits the same GPU-free harness the pytest session
+    uses (device_type stubs plus torch.cuda probe patches). Without it,
+    ``import unsloth.registry`` raises ``NotImplementedError`` from
+    ``unsloth_zoo.device_type`` on no-accelerator CI runners, so the child
+    would exit non-zero and the test would fail even though the registry code
+    is correct. A fresh process also keeps each check independent of any
+    ``register_models()`` calls other tests make on the shared registry.
+    """
+    tests_dir = os.path.dirname(os.path.abspath(__file__))
+    prelude = (
+        f"import sys; sys.path.insert(0, {tests_dir!r})\n"
+        "try:\n"
+        "    import conftest  # noqa: F401  GPU-free harness on no-accelerator runners\n"
+        "except Exception:\n"
+        "    pass\n"
+    )
+    return subprocess.run(
+        [sys.executable, "-c", prelude + body],
+        capture_output = True,
+        text = True,
+        check = False,
+    )
+
+
+def test_importing_registry_does_not_register_models():
+    """Importing the registry must not populate MODEL_REGISTRY on its own.
+
+    ``_deepseek`` used to call ``register_deepseek_models(...)`` at module
+    scope, so merely importing ``unsloth.registry`` registered models as an
+    import side effect, unlike every other family which only registers on
+    demand.
+    """
+    result = _run_registry_child(
+        "import unsloth.registry\n"
+        "from unsloth.registry.registry import MODEL_REGISTRY\n"
+        "print('REGISTRY_SIZE', len(MODEL_REGISTRY))"
+    )
+    assert result.returncode == 0, (
+        f"registry import subprocess exited {result.returncode}\n"
+        f"stdout:\n{result.stdout}\nstderr:\n{result.stderr}"
+    )
+    size_lines = [line for line in result.stdout.splitlines() if line.startswith("REGISTRY_SIZE")]
+    assert size_lines == ["REGISTRY_SIZE 0"], result.stdout + result.stderr
+
+
+def test_register_models_registers_no_upstream_originals():
+    """``register_models()`` must register each family's ``unsloth``-org models
+    and must NOT leak upstream vendor "original" models.
+
+    Before the fix, ``_deepseek``'s import-time
+    ``register_deepseek_models(include_original_model = True)`` set the
+    ``_IS_DEEPSEEK_*_REGISTERED`` guards, so the later default
+    ``register_models()`` early-returned for deepseek and its 10 ``deepseek-ai``
+    originals leaked permanently (129 -> 139). This asserts the whole registry
+    is ``unsloth``-org after ``register_models()`` while deepseek is still
+    registered via the normal path. Runs in a fresh interpreter so it is
+    independent of other tests' registry mutations.
+    """
+    result = _run_registry_child(
+        "import unsloth.registry\n"
+        "from unsloth.registry import register_models\n"
+        "from unsloth.registry.registry import MODEL_REGISTRY\n"
+        "register_models()\n"
+        "orgs = sorted({m.org for m in MODEL_REGISTRY.values()})\n"
+        "deepseek = [k for k in MODEL_REGISTRY if 'deepseek' in k.lower()]\n"
+        "print('ORGS', orgs)\n"
+        "print('NUM_DEEPSEEK', len(deepseek))"
+    )
+    assert result.returncode == 0, (
+        f"register_models subprocess exited {result.returncode}\n"
+        f"stdout:\n{result.stdout}\nstderr:\n{result.stderr}"
+    )
+    out = result.stdout
+    # Every registered model is unsloth-org: no upstream "original" leaked.
+    assert "ORGS ['unsloth']" in out, out + result.stderr
+    # Deepseek is still registered via the normal path, just without originals.
+    deepseek_lines = [line for line in out.splitlines() if line.startswith("NUM_DEEPSEEK")]
+    assert deepseek_lines and int(deepseek_lines[0].split()[1]) > 0, out + result.stderr
diff --git a/unsloth/registry/_deepseek.py b/unsloth/registry/_deepseek.py
index e29190f0f2..618453fb82 100644
--- a/unsloth/registry/_deepseek.py
+++ b/unsloth/registry/_deepseek.py
@@ -171,8 +171,6 @@ def _list_deepseek_r1_distill_models():
     return distill_models
 
 
-register_deepseek_models(include_original_model = True)
-
 if __name__ == "__main__":
     from unsloth.registry.registry import MODEL_REGISTRY, _check_model_info