diff --git a/cpdfcommand.ml b/cpdfcommand.ml
index ab32cb3..bc3ab02 100644
--- a/cpdfcommand.ml
+++ b/cpdfcommand.ml
@@ -3032,6 +3032,7 @@ let specs =
    ("-print-struct-tree", Arg.Unit (fun () -> setop PrintStructTree ()), " Print structure tree");
    ("-extract-struct-tree", Arg.Unit (fun () -> setop ExtractStructTree ()), " Extract structure tree in JSON format");
    ("-replace-struct-tree", Arg.String (fun s -> setop (ReplaceStructTree s) ()), " Replace structure tree from JSON");
+   ("-remove-struct-tree", Arg.Unit (fun () -> setop RemoveStructTree ()), " Remove entire structure tree");
    ("-redact", Arg.Unit (fun () -> setop Redact ()), " Redact entire pages");
    ("-rasterize", Arg.Unit (fun () -> setop Rasterize ()), " Rasterize pages");
    ("-rasterize-gray", Arg.Unit (fun () -> args.rast_device <- "pnggray"), " Rasterize in grayscale");
@@ -4895,7 +4896,7 @@ let go () =
         write_pdf false pdf
   | Some RemoveStructTree ->
       let pdf = get_single_pdf args.op false in
-        Cpdfua.remove_struct_tree pdf;
+      let pdf = Cpdfua.remove_struct_tree pdf in
         write_pdf false pdf
   | Some (SetLanguage s) ->
       let pdf = get_single_pdf args.op false in
diff --git a/cpdftweak.ml b/cpdftweak.ml
index 4e67b77..96da311 100644
--- a/cpdftweak.ml
+++ b/cpdftweak.ml
@@ -92,7 +92,7 @@ let blacktext c range pdf =
   in
     Cpdfpage.process_pages (Pdfpage.ppstub blacktext_page) pdf range
 
-(* Blacken lines *)
+(* Blacken lines. FIXME Why doesn't this do xobjects like the other two? *)
 let blacklines_ops c pdf resources content =
   let rec blacken_strokeops prev = function
     | [] -> rev prev
diff --git a/cpdfua.ml b/cpdfua.ml
index e296d7c..56efe78 100644
--- a/cpdfua.ml
+++ b/cpdfua.ml
@@ -1835,7 +1835,7 @@ let create_pdfua1 title pagesize pages =
     let pdf = Cpdfmetadata.set_viewer_preference ("/DisplayDocTitle", Pdf.Boolean true, 0) pdf in
       Pdf.replace_chain pdf ["/Root"; "/MarkInfo"; "/Marked"] (Pdf.Boolean true);
       Pdf.replace_chain pdf ["/Root"; "/StructTreeRoot"; "/Type"] (Pdf.Name "/StructTreeRoot");
-      let pdf = {pdf with Pdf.major = 1; Pdf.minor =  7} in
+      let pdf = {pdf with Pdf.major = 1; Pdf.minor = 7} in
         mark pdf;
         pdf
 
@@ -1847,8 +1847,32 @@ let create_pdfua2 title pagesize pages =
     let pdf = Cpdfmetadata.set_viewer_preference ("/DisplayDocTitle", Pdf.Boolean true, 0) pdf in
       Pdf.replace_chain pdf ["/Root"; "/MarkInfo"; "/Marked"] (Pdf.Boolean true);
       Pdf.replace_chain pdf ["/Root"; "/StructTreeRoot"; "/Type"] (Pdf.Name "/StructTreeRoot");
-      let pdf = {pdf with Pdf.major = 2; Pdf.minor =  0} in
+      let pdf = {pdf with Pdf.major = 2; Pdf.minor = 0} in
         mark2 2024 pdf;
         pdf
 
-let remove_struct_tree pdf = ()
+let remove_struct_tree pdf =
+  Cpdftweak.remove_dict_entry pdf "/StructTreeRoot" None;
+  Cpdftweak.remove_dict_entry pdf "/StructParent" None;
+  Cpdftweak.remove_dict_entry pdf "/StructParents" None;
+  let remove_struct_tree_ops pdf resources content =
+    let operators = Pdfops.parse_operators pdf resources content in
+    (* In fact, we remove all marked content regions. Acceptable in the circumstances. *)
+    let remove_mcids =
+      lose
+        (function
+         | Pdfops.Op_MP _
+         | Pdfops.Op_DP _
+         | Pdfops.Op_BMC _
+         | Pdfops.Op_BDC _
+         | Pdfops.Op_EMC -> true | _ -> false)
+    in
+    let operators' = remove_mcids operators in
+      [Pdfops.stream_of_ops operators']
+  in
+  let remove_struct_tree_page _ page =
+    let content' = remove_struct_tree_ops pdf page.Pdfpage.resources page.Pdfpage.content in
+      Pdfpage.process_xobjects pdf page remove_struct_tree_ops;
+      {page with Pdfpage.content = content'}
+  in
+    Cpdfpage.process_pages (Pdfpage.ppstub remove_struct_tree_page) pdf (ilist 1 (Pdfpage.endpage pdf))
diff --git a/cpdfua.mli b/cpdfua.mli
index 8d1d1b5..d73f096 100644
--- a/cpdfua.mli
+++ b/cpdfua.mli
@@ -32,7 +32,7 @@ val extract_struct_tree : Pdf.t -> Cpdfyojson.Safe.t
 val replace_struct_tree : Pdf.t -> Cpdfyojson.Safe.t -> unit
 
 (** Remove a structure tree entirely from a file, including unmarking marked content. *)
-val remove_struct_tree : Pdf.t -> unit
+val remove_struct_tree : Pdf.t -> Pdf.t
 
 (** Make a blank PDF/UA-1 PDF given a title, paper size, and number of pages. *)
 val create_pdfua1 : string -> Pdfpaper.t -> int -> Pdf.t
diff --git a/cpdfxobject.ml b/cpdfxobject.ml
index 3108caa..a81de19 100644
--- a/cpdfxobject.ml
+++ b/cpdfxobject.ml
@@ -85,4 +85,3 @@ let stamp_as_xobject pdf range over =
                     let pdf = Pdfmarks.add_bookmarks new_marks changed in
                     let name = "/" ^ Pdfpage.shortest_unused_prefix pdf ^ "CPDFXObj" in
                       (add_page_as_xobject pdf range over_page name, name)
-