diff --git a/.changeset/mean-pens-grow.md b/.changeset/mean-pens-grow.md
new file mode 100644
index 0000000000..771d67c9d4
--- /dev/null
+++ b/.changeset/mean-pens-grow.md
@@ -0,0 +1,5 @@
+---
+"@khanacademy/perseus": patch
+---
+
+Internal: Add regression tests for PerseusItem parser
diff --git a/packages/perseus/src/util/parse-perseus-json/perseus-parsers/radio-widget.ts b/packages/perseus/src/util/parse-perseus-json/perseus-parsers/radio-widget.ts
index b1ad09b5ed..4678fdaf8b 100644
--- a/packages/perseus/src/util/parse-perseus-json/perseus-parsers/radio-widget.ts
+++ b/packages/perseus/src/util/parse-perseus-json/perseus-parsers/radio-widget.ts
@@ -43,6 +43,6 @@ export const parseRadioWidget: Parser<RadioWidget> = parseWidget(
         displayCount: optional(any),
         // v0 props
         // `noneOfTheAbove` is still in use (but only set to `false`).
-        noneOfTheAbove: constant(false),
+        noneOfTheAbove: optional(constant(false)),
     }),
 );
diff --git a/packages/perseus/src/util/parse-perseus-json/regression-tests/data/radio-missing-noneOfTheAbove.json b/packages/perseus/src/util/parse-perseus-json/regression-tests/data/radio-missing-noneOfTheAbove.json
new file mode 100644
index 0000000000..ed463b51a8
--- /dev/null
+++ b/packages/perseus/src/util/parse-perseus-json/regression-tests/data/radio-missing-noneOfTheAbove.json
@@ -0,0 +1,48 @@
+{
+  "question": {
+    "content": "$\\begin{align} \nA &= \\{x: x \\text{ is a rectangle in the plane P} \\} \\\\\\\\\nB &= \\{x: x \\text{ is a square in the plane P} \\}\n\\end{align}$\n\n**Is $A \\subset B$ ?**\n\n[[☃ radio 1]]\n",
+    "images": {},
+    "widgets": {
+      "radio 1": {
+        "type": "radio",
+        "alignment": "default",
+        "static": false,
+        "graded": true,
+        "options": {
+          "choices": [
+            {
+              "content": "Yes",
+              "correct": false
+            },
+            {
+              "content": "No",
+              "correct": true
+            }
+          ],
+          "randomize": false,
+          "multipleSelect": false,
+          "countChoices": false,
+          "displayCount": null,
+          "hasNoneOfTheAbove": false,
+          "deselectEnabled": false
+        },
+        "version": {
+          "major": 1,
+          "minor": 0
+        }
+      }
+    }
+  },
+  "answerArea": {
+    "calculator": false,
+    "chi2Table": false,
+    "periodicTable": false,
+    "tTable": false,
+    "zTable": false
+  },
+  "itemDataVersion": {
+    "major": 0,
+    "minor": 1
+  },
+  "hints": []
+}
diff --git a/packages/perseus/src/util/parse-perseus-json/regression-tests/parse-perseus-json-regression.test.ts b/packages/perseus/src/util/parse-perseus-json/regression-tests/parse-perseus-json-regression.test.ts
new file mode 100644
index 0000000000..96a2b1b32d
--- /dev/null
+++ b/packages/perseus/src/util/parse-perseus-json/regression-tests/parse-perseus-json-regression.test.ts
@@ -0,0 +1,20 @@
+import * as fs from "fs";
+import {join} from "path";
+
+import {parseAndTypecheckPerseusItem} from "../index";
+
+const dataFiles = fs.readdirSync(join(__dirname, "data"));
+
+describe("parseAndTypecheckPerseusItem", () => {
+    it.each(dataFiles)("accepts data/%s", (filename) => {
+        const json = fs.readFileSync(
+            join(__dirname, "data", filename),
+            "utf-8",
+        );
+        const result = parseAndTypecheckPerseusItem(json);
+
+        // This strange-looking assertion style results in the failure message
+        // being printed if parsing fails, so the test is easier to debug.
+        expect(result).toEqual(expect.objectContaining({type: "success"}));
+    });
+});