diff --git a/CHANGELOG.md b/CHANGELOG.md
index f248217..c7aef2c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.0.14]
+
+### Fixed
+
+- The `Distribution` API now handles ZIP source distributions
+  (those ending with `.zip`) instead of rejecting them as invalid
+  ([#68](https://github.com/trailofbits/pypi-attestations/pull/68))
+
 ## [0.0.13]
 
 ### Changed
@@ -155,7 +163,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Initial implementation
 
-[Unreleased]: https://github.com/trailofbits/pypi-attestation-models/compare/v0.0.13...HEAD
+[Unreleased]: https://github.com/trailofbits/pypi-attestation-models/compare/v0.0.14...HEAD
+[0.0.14]: https://github.com/trailofbits/pypi-attestation-models/compare/v0.0.13...v0.0.14
 [0.0.13]: https://github.com/trailofbits/pypi-attestation-models/compare/v0.0.12...v0.0.13
 [0.0.12]: https://github.com/trailofbits/pypi-attestation-models/compare/v0.0.11...v0.0.12
 [0.0.11]: https://github.com/trailofbits/pypi-attestation-models/compare/v0.0.10...v0.0.11
diff --git a/src/pypi_attestations/_impl.py b/src/pypi_attestations/_impl.py
index ad93a46..0f6355c 100644
--- a/src/pypi_attestations/_impl.py
+++ b/src/pypi_attestations/_impl.py
@@ -374,12 +374,15 @@ def _ultranormalize_dist_filename(dist: str) -> str:
             parts = "-".join([name, str(ver), impl_tag, abi_tag, platform_tag])
 
         return f"{parts}.whl"
-
-    elif dist.endswith(".tar.gz"):
+    elif dist.endswith((".tar.gz", ".zip")):
         # `parse_sdist_filename` raises a supertype of ValueError on failure.
         name, ver = parse_sdist_filename(dist)
         name = name.replace("-", "_")
-        return f"{name}-{ver}.tar.gz"
+
+        if dist.endswith(".tar.gz"):
+            return f"{name}-{ver}.tar.gz"
+        else:
+            return f"{name}-{ver}.zip"
     else:
         raise ValueError(f"unknown distribution format: {dist}")
 
diff --git a/test/test_impl.py b/test/test_impl.py
index 109d5bc..745f244 100644
--- a/test/test_impl.py
+++ b/test/test_impl.py
@@ -457,10 +457,14 @@ def test_exception_types(self) -> None:
         ("foo-1.0-py3-none.none.none-any.whl", "foo-1.0-py3-none-any.whl"),
         # sdist: fully normalized, no changes
         ("foo-1.0.tar.gz", "foo-1.0.tar.gz"),
+        ("foo-1.0.zip", "foo-1.0.zip"),
         # sdist: dist name is not case normalized
         ("Foo-1.0.tar.gz", "foo-1.0.tar.gz"),
         ("FOO-1.0.tar.gz", "foo-1.0.tar.gz"),
         ("FoO-1.0.tar.gz", "foo-1.0.tar.gz"),
+        ("Foo-1.0.zip", "foo-1.0.zip"),
+        ("FOO-1.0.zip", "foo-1.0.zip"),
+        ("FoO-1.0.zip", "foo-1.0.zip"),
         # sdist: dist name contains alternate separators, including
         # `-` despite being forbidden by PEP 625
         ("foo-bar-1.0.tar.gz", "foo_bar-1.0.tar.gz"),
@@ -469,9 +473,17 @@ def test_exception_types(self) -> None:
         ("foo.bar-1.0.tar.gz", "foo_bar-1.0.tar.gz"),
         ("foo..bar-1.0.tar.gz", "foo_bar-1.0.tar.gz"),
         ("foo.bar.baz-1.0.tar.gz", "foo_bar_baz-1.0.tar.gz"),
+        ("foo-bar-1.0.zip", "foo_bar-1.0.zip"),
+        ("foo-bar-baz-1.0.zip", "foo_bar_baz-1.0.zip"),
+        ("foo--bar-1.0.zip", "foo_bar-1.0.zip"),
+        ("foo.bar-1.0.zip", "foo_bar-1.0.zip"),
+        ("foo..bar-1.0.zip", "foo_bar-1.0.zip"),
+        ("foo.bar.baz-1.0.zip", "foo_bar_baz-1.0.zip"),
         # sdist: dist version is not normalized
         ("foo-1.0beta1.tar.gz", "foo-1.0b1.tar.gz"),
         ("foo-01.0beta1.tar.gz", "foo-1.0b1.tar.gz"),
+        ("foo-1.0beta1.zip", "foo-1.0b1.zip"),
+        ("foo-01.0beta1.zip", "foo-1.0b1.zip"),
     ],
 )
 def test_ultranormalize_dist_filename(input: str, normalized: str) -> None:
@@ -489,6 +501,7 @@ def test_ultranormalize_dist_filename(input: str, normalized: str) -> None:
         "foo",
         # suffixes must be lowercase
         "foo-1.0.TAR.GZ",
+        "foo-1.0.ZIP",
         "foo-1.0-py3-none-any.WHL",
         # wheel: invalid separator in dist name
         "foo-bar-1.0-py3-none-any.whl",
@@ -499,6 +512,13 @@ def test_ultranormalize_dist_filename(input: str, normalized: str) -> None:
         # sdist: invalid version
         "foo-charmander.tar.gz",
         "foo-1charmander.tar.gz",
+        "foo-charmander.zip",
+        "foo-1charmander.zip",
+        # sdist: nonsense suffixes
+        "foo-1.2.3.junk.zip",
+        "foo-1.2.3.junk.tar.gz",
+        "foo-1.2.3.zip.tar.gz",
+        "foo-1.2.3.tar.gz.zip",
     ],
 )
 def test_ultranormalize_dist_filename_invalid(input: str) -> None: