diff --git a/lib/LaTeXML/Engine/TeX_Box.pool.ltxml b/lib/LaTeXML/Engine/TeX_Box.pool.ltxml
index 56ae014d9..856baada0 100644
--- a/lib/LaTeXML/Engine/TeX_Box.pool.ltxml
+++ b/lib/LaTeXML/Engine/TeX_Box.pool.ltxml
@@ -415,7 +415,11 @@ sub insertBlock {
 
 DefConstructor('\vbox BoxSpecification VBoxContents', sub {
     my ($document, $spec, $contents, %props) = @_;
-    my @block = insertBlock($document, $contents, vattach => 'bottom'); },
+    # Note: passing in empty block_props allows insertBlock to unwrap the container node entirely,
+    #       which is often desired in cases such as \unvbox,
+    #       and can be requested by setting "_unwrapped_block".
+    my %block_props = $props{'_unwrapped_block'} ? () : (vattach => 'bottom');
+    my @block       = insertBlock($document, $contents, %block_props); },
   sizer       => '#2',
   properties  => { layout => 'vertical', vattach => 'bottom' },
   mode        => 'text',
@@ -432,7 +436,8 @@ DefConstructor('\vbox BoxSpecification VBoxContents', sub {
 
 DefConstructor('\vtop BoxSpecification VBoxContents', sub {
     my ($document, $spec, $contents, %props) = @_;
-    insertBlock($document, $contents, vattach => 'top'); },
+    my %block_props = $props{'_unwrapped_block'} ? () : (vattach => 'top');
+    insertBlock($document, $contents, %block_props); },
   sizer       => '#2',
   properties  => { layout => 'vertical', vattach => 'baseline' },
   mode        => 'text',
@@ -574,13 +579,23 @@ DefPrimitive('\unhbox Number', sub {
     my $stuff = LookupValue($box);
     adjustBoxColor($stuff);
     AssignValue($box, undef);
-    (defined $stuff ? $stuff->unlist : List()); });
+    if (ref $stuff eq 'LaTeXML::Core::Whatsit') {
+      $stuff->setProperty("_unwrapped_block" => 1);
+      return $stuff;
+    } else {
+      return (defined $stuff ? $stuff->unlist : List());
+} });
 
 DefPrimitive('\unhcopy Number', sub {
     my $box   = 'box' . $_[1]->valueOf;
     my $stuff = LookupValue($box);
     adjustBoxColor($stuff);
-    (defined $stuff ? $stuff->unlist : List()); });
+    if (ref $stuff eq 'LaTeXML::Core::Whatsit') {
+      $stuff->setProperty("_unwrapped_block" => 1);
+      return $stuff;
+    } else {
+      return (defined $stuff ? $stuff->unlist : List());
+} });
 
 # \unvbox<8bit>, \unvcopy<8bit>
 DefPrimitive('\unvbox Number', sub {
@@ -588,13 +603,23 @@ DefPrimitive('\unvbox Number', sub {
     my $stuff = LookupValue($box);
     adjustBoxColor($stuff);
     AssignValue($box, undef);
-    (defined $stuff ? $stuff->unlist : List()); });
+    if (ref $stuff eq 'LaTeXML::Core::Whatsit') {
+      $stuff->setProperty("_unwrapped_block" => 1);
+      return $stuff;
+    } else {
+      return (defined $stuff ? $stuff->unlist : List());
+} });
 
 DefPrimitive('\unvcopy Number', sub {
     my $box   = 'box' . $_[1]->valueOf;
     my $stuff = LookupValue($box);
     adjustBoxColor($stuff);
-    (defined $stuff ? $stuff->unlist : List()); });
+    if (ref $stuff eq 'LaTeXML::Core::Whatsit') {
+      $stuff->setProperty("_unwrapped_block" => 1);
+      return $stuff;
+    } else {
+      return (defined $stuff ? $stuff->unlist : List());
+} });
 
 #%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 # Various box related parameters
diff --git a/t/alignment/vmode.pdf b/t/alignment/vmode.pdf
index 84bb2dc4d..3acc5a968 100644
Binary files a/t/alignment/vmode.pdf and b/t/alignment/vmode.pdf differ
diff --git a/t/alignment/vmode.tex b/t/alignment/vmode.tex
index 638a39100..d260dbf5f 100644
--- a/t/alignment/vmode.tex
+++ b/t/alignment/vmode.tex
@@ -84,4 +84,18 @@ \section{Graphics rescaling}
 
 \scalebox{3}[2]{\includegraphics{foo}}
 
+\section{unvbox and unvcopy}
+%
+\newbox\boxA
+\newbox\boxB
+\newbox\boxC
+\newbox\boxD
+\newbox\boxE
+\setbox\boxA=\vbox spread 1cm{1cm Box}
+\setbox\boxB=\vbox spread 2cm{2cm Box}
+\setbox\boxC=\vbox{\unvcopy\boxA\unvcopy\boxB}
+\setbox\boxD=\vbox{\unvbox\boxA\unvbox\boxB}
+\setbox\boxE=\vbox{\unvbox\boxC\unvbox\boxD}
+%
+via unvbox, unvcopy: \fbox{\box\boxE}
 \end{document}
\ No newline at end of file
diff --git a/t/alignment/vmode.xml b/t/alignment/vmode.xml
index c618ee2d6..283702621 100644
--- a/t/alignment/vmode.xml
+++ b/t/alignment/vmode.xml
@@ -205,4 +205,20 @@ This is random text. This is random text. This is random text.</p>
       </inline-block>
     </para>
   </section>
+  <section inlist="toc" xml:id="S5">
+    <tags>
+      <tag>5</tag>
+      <tag role="refnum">5</tag>
+      <tag role="typerefnum">§5</tag>
+    </tags>
+    <title><tag close=" ">5</tag>unvbox and unvcopy</title>
+    <para xml:id="S5.p1">
+      <p>via unvbox, unvcopy: <inline-block framed="rectangle" vattach="bottom">
+          <p>1cm Box</p>
+          <p>2cm Box</p>
+          <p>1cm Box</p>
+          <p>2cm Box</p>
+        </inline-block></p>
+    </para>
+  </section>
 </document>