diff --git a/README.md b/README.md
index 19c8ac8b1..f4f893856 100644
--- a/README.md
+++ b/README.md
@@ -89,6 +89,10 @@ Made with [contrib.rocks](https://contrib.rocks).
 
 ### bioimageio.spec Python package
 
+#### bioimageio.spec 0.5.2post4 (to be released)
+
+* resolve backup DOIs
+
 #### bioimageio.spec 0.5.2post3
 
 * avoid full download when validating urls
diff --git a/bioimageio/spec/_internal/io_utils.py b/bioimageio/spec/_internal/io_utils.py
index 9c0cb6d8a..64e60d896 100644
--- a/bioimageio/spec/_internal/io_utils.py
+++ b/bioimageio/spec/_internal/io_utils.py
@@ -200,6 +200,11 @@ def _get_one_collection(url: str):
         # set version specific entry
         ret[c_entry.id + "/" + str(entry["version_number"])] = c_entry
 
+        # set doi entry
+        doi = entry.get("doi")
+        if doi is not None:
+            ret[doi] = c_entry
+
         # update 'latest version' entry
         if c_entry.id not in ret:
             update = True
@@ -216,6 +221,10 @@ def _get_one_collection(url: str):
 
         if update:
             ret[c_entry.id] = c_entry
+            # set concept doi entry
+            concept_doi = entry.get("concept_doi")
+            if concept_doi is not None:
+                ret[concept_doi] = c_entry
 
     return ret
 
diff --git a/tests/test_io.py b/tests/test_io.py
index 8b3b6339a..571942cce 100644
--- a/tests/test_io.py
+++ b/tests/test_io.py
@@ -17,6 +17,8 @@ def test_load_non_existing_rdf():
     [
         "invigorating-lab-coat",
         "invigorating-lab-coat/1",
+        "10.5281/zenodo.11092896",  # backup doi of version 1
+        "10.5281/zenodo.11092895",  # concept doi of backup
         "invigorating-lab-coat/staged/1",
     ],
 )
@@ -25,4 +27,4 @@ def test_load_by_id(rid: str):
 
     model = load_description(rid)
     assert not isinstance(model, InvalidDescr)
-    assert model.id == rid.split("/")[0]
+    assert model.id == "invigorating-lab-coat"