diff --git a/poi-ooxml/src/main/java/org/apache/poi/openxml4j/opc/PackagePartCollection.java b/poi-ooxml/src/main/java/org/apache/poi/openxml4j/opc/PackagePartCollection.java
index a5f3dfc258..c22fa1f68d 100644
--- a/poi-ooxml/src/main/java/org/apache/poi/openxml4j/opc/PackagePartCollection.java
+++ b/poi-ooxml/src/main/java/org/apache/poi/openxml4j/opc/PackagePartCollection.java
@@ -65,7 +65,7 @@ public final class PackagePartCollection implements Serializable {
         final String ppName = partName.getName();
         final StringBuilder concatSeg = new StringBuilder();
         // split at slash, but keep leading slash
-        final String delim = "(?=["+PackagingURIHelper.FORWARD_SLASH_STRING+".])";
+        final String delim = "(?=["+PackagingURIHelper.FORWARD_SLASH_STRING+"])";
         for (String seg : ppName.split(delim)) {
             concatSeg.append(seg);
             if (registerPartNameStr.contains(concatSeg.toString())) {
diff --git a/poi-ooxml/src/test/java/org/apache/poi/openxml4j/opc/TestPackagePartCollection.java b/poi-ooxml/src/test/java/org/apache/poi/openxml4j/opc/TestPackagePartCollection.java
new file mode 100644
index 0000000000..f64d582c12
--- /dev/null
+++ b/poi-ooxml/src/test/java/org/apache/poi/openxml4j/opc/TestPackagePartCollection.java
@@ -0,0 +1,45 @@
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+
+package org.apache.poi.openxml4j.opc;
+
+import static org.apache.poi.openxml4j.OpenXML4JTestDataSamples.openSampleStream;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.InputStream;
+import java.util.List;
+import java.util.regex.Pattern;
+
+import org.junit.jupiter.api.Test;
+
+public class TestPackagePartCollection {
+
+    @Test
+    void testPackagePartCollection_64473() throws Exception {
+        InputStream is = openSampleStream("64473.xlsx");
+        try (OPCPackage pkg = OPCPackage.open(is)) {
+            List<PackagePart> allParts = pkg.getParts();
+            assertEquals(15, allParts.size());
+            List<PackagePart> partsByName = pkg.getPartsByName(Pattern.compile("/xl/metadata.*"));
+            // contains the following parts:
+            // /xl/metadata
+            // /xl/metadata.xml
+            assertEquals(2, partsByName.size());
+        }
+    }
+
+}
diff --git a/test-data/openxml4j/64473.xlsx b/test-data/openxml4j/64473.xlsx
new file mode 100644
index 0000000000..a20756d692
Binary files /dev/null and b/test-data/openxml4j/64473.xlsx differ