diff --git a/src/enc/block_splitter.rs b/src/enc/block_splitter.rs
index 9e9fe78f..63227922 100755
--- a/src/enc/block_splitter.rs
+++ b/src/enc/block_splitter.rs
@@ -124,7 +124,7 @@ fn CountLiterals(cmds: &[Command], num_commands: usize) -> usize {
 }
 
 fn CommandCopyLen(xself: &Command) -> u32 {
-    xself.copy_len_ & 0xffffffu32
+    xself.copy_len_ & 0x1ffffffu32
 }
 
 fn CopyLiteralsToByteArray(
diff --git a/src/enc/brotli_bit_stream.rs b/src/enc/brotli_bit_stream.rs
index 8d0c4f7a..fb4eb79a 100755
--- a/src/enc/brotli_bit_stream.rs
+++ b/src/enc/brotli_bit_stream.rs
@@ -2145,7 +2145,7 @@ fn StoreSymbolWithContext<Alloc: alloc::Allocator<u8> + alloc::Allocator<u16>>(
 }
 
 fn CommandCopyLen(xself: &Command) -> u32 {
-    xself.copy_len_ & 0xffffffu32
+  xself.copy_len_ & 0x1ffffffu32
 }
 
 fn CommandDistanceContext(xself: &Command) -> u32 {