diff --git a/test/calendar.test.js b/test/calendar.test.js
index ba38d1d..3f5bf10 100644
--- a/test/calendar.test.js
+++ b/test/calendar.test.js
@@ -34,6 +34,31 @@ describe('Calendar Merging API', () => {
         return fs.readFileSync(path.join(EXPECTED_OUTPUTS_DIR, filename), 'utf8');
     };
 
+    test('Preserve date-based calendar', async () => {
+        const input = loadCalendarFile('US_Holidays.ics');
+        const response = await request(server)
+            .post('/merge')
+            .send({
+                linkGroupName: 'US Holidays',
+                calendars: [
+                    {
+                        url: input,
+                        prefix: '',
+                        override: false,
+                    },
+                ],
+            });
+        expect(response.status).toBe(200);
+        // Check if the file was created in the test directory
+        const filePath = path.join(CALENDARS_DIR, 'US_Holidays.ics');
+        console.log('Checking if file exists at:', filePath);
+        expect(fs.existsSync(filePath)).toBe(true);
+        // Load expected output and compare
+        const expectedOutput = fs.readFileSync(input, 'utf8');
+        const actualOutput = fs.readFileSync(filePath, 'utf8');
+        expect(actualOutput).toBe(expectedOutput);
+    });
+
     test('Merge date-based calendar', async () => {
         const response = await request(server)
             .post('/merge')
diff --git a/test/expected_outputs/Date_Based_Calendar.ics b/test/expected_outputs/Date_Based_Calendar.ics
index 601e75d..d54023b 100644
--- a/test/expected_outputs/Date_Based_Calendar.ics
+++ b/test/expected_outputs/Date_Based_Calendar.ics
@@ -1,5 +1,4 @@
 BEGIN:VCALENDAR
-PRODID:-//Your Product ID//EN
 VERSION:2.0
 NAME:Date Based Calendar
 BEGIN:VEVENT
@@ -14,4 +13,4 @@ SUMMARY:US_holidays Christmas Day
 DTSTART:20231225T000000
 DTEND:20231226T000000
 END:VEVENT
-END:VCALENDAR
\ No newline at end of file
+END:VCALENDAR
diff --git a/test/test_calendars/US_Holidays.ics b/test/test_calendars/US_Holidays.ics
index 8d20aa7..d8ace67 100644
--- a/test/test_calendars/US_Holidays.ics
+++ b/test/test_calendars/US_Holidays.ics
@@ -1,15 +1,11 @@
 BEGIN:VCALENDAR
+NAME:US Holidays
 VERSION:2.0
-PRODID:-//Example Corp//NONSGML Event//EN
 BEGIN:VEVENT
 UID:20231225T000000-001@example.com
 DTSTAMP:20231225T000000Z
 DTSTART;VALUE=DATE:20231225
 DTEND;VALUE=DATE:20231226
 SUMMARY:Christmas Day
-DESCRIPTION:Public holiday for Christmas in The US.
-LOCATION:San Francisco
-STATUS:CONFIRMED
-SEQUENCE:0
 END:VEVENT
 END:VCALENDAR