diff --git a/parquet-column/src/test/java/org/apache/parquet/column/values/dictionary/TestDictionary.java b/parquet-column/src/test/java/org/apache/parquet/column/values/dictionary/TestDictionary.java
index 13033404ce..929d95f2a9 100644
--- a/parquet-column/src/test/java/org/apache/parquet/column/values/dictionary/TestDictionary.java
+++ b/parquet-column/src/test/java/org/apache/parquet/column/values/dictionary/TestDictionary.java
@@ -45,6 +45,7 @@
 import org.apache.parquet.column.values.dictionary.DictionaryValuesWriter.PlainFloatDictionaryValuesWriter;
 import org.apache.parquet.column.values.dictionary.DictionaryValuesWriter.PlainIntegerDictionaryValuesWriter;
 import org.apache.parquet.column.values.dictionary.DictionaryValuesWriter.PlainLongDictionaryValuesWriter;
+import org.apache.parquet.column.values.dictionary.PlainValuesDictionary.PlainBinaryDictionary;
 import org.apache.parquet.column.values.dictionary.PlainValuesDictionary.PlainBooleanDictionary;
 import org.apache.parquet.column.values.fallback.FallbackValuesWriter;
 import org.apache.parquet.column.values.plain.BinaryPlainValuesReader;
@@ -803,6 +804,17 @@ public void testZeroValues() throws IOException {
     }
   }
 
+  @Test
+  public void testDictionaryPageCopyDoesNotAliasSourceBytes() throws IOException {
+    byte[] source = {1, 0, 0, 0, 'a'};
+    DictionaryPage copied = new DictionaryPage(BytesInput.from(source), 1, PLAIN).copy();
+
+    source[4] = 'b';
+
+    PlainBinaryDictionary dictionary = new PlainBinaryDictionary(copied);
+    assertThat(dictionary.decodeToBinary(0).toStringUsingUTF8()).isEqualTo("a");
+  }
+
   @Test
   public void testBooleanDictionary() throws IOException {
     // Create a dictionary page with boolean values (false, true)
diff --git a/parquet-common/src/main/java/org/apache/parquet/bytes/BytesInput.java b/parquet-common/src/main/java/org/apache/parquet/bytes/BytesInput.java
index ca139d9243..89c1bca4d8 100644
--- a/parquet-common/src/main/java/org/apache/parquet/bytes/BytesInput.java
+++ b/parquet-common/src/main/java/org/apache/parquet/bytes/BytesInput.java
@@ -690,18 +690,9 @@ public ByteBuffer toByteBuffer() throws IOException {
       return java.nio.ByteBuffer.wrap(in, offset, length);
     }
 
-    /**
-     * Zero-copy override: returns the backing array directly when fully used,
-     * skipping the base-class BAOS allocation + copy on every decompressor call.
-     * Returning the mutable array is safe — the base class already exposes a
-     * mutable {@code BAOS.getBuf()}.
-     */
     @SuppressWarnings("deprecation")
     @Override
     public byte[] toByteArray() {
-      if (offset == 0 && length == in.length) {
-        return in;
-      }
       return Arrays.copyOfRange(in, offset, offset + length);
     }
 
diff --git a/parquet-common/src/test/java/org/apache/parquet/bytes/TestBytesInput.java b/parquet-common/src/test/java/org/apache/parquet/bytes/TestBytesInput.java
index a80c874fa2..2eb8aac413 100644
--- a/parquet-common/src/test/java/org/apache/parquet/bytes/TestBytesInput.java
+++ b/parquet-common/src/test/java/org/apache/parquet/bytes/TestBytesInput.java
@@ -123,16 +123,16 @@ public void testFromByteArray(ByteBufferAllocator innerAllocator) throws IOExcep
 
   @ParameterizedTest(name = "{0}")
   @MethodSource("parameters")
-  public void testFromByteArrayToByteArrayZeroCopy(ByteBufferAllocator innerAllocator) throws IOException {
+  public void testFromByteArrayToByteArrayCopiesFullArray(ByteBufferAllocator innerAllocator) throws IOException {
     initAllocator(innerAllocator);
-    // Full array (offset=0, length=array.length): toByteArray() returns the backing array directly
     byte[] data = new byte[1000];
     RANDOM.nextBytes(data);
     BytesInput bi = BytesInput.from(data, 0, data.length);
     byte[] result = bi.toByteArray();
     assertThat(result)
-        .as("toByteArray() should return the backing array when offset=0 and length=full")
-        .isSameAs(data);
+        .as("toByteArray() should materialize a copy when offset=0 and length=full")
+        .isEqualTo(data)
+        .isNotSameAs(data);
   }
 
   @ParameterizedTest(name = "{0}")