diff --git a/doc/ChangeLog.txt b/doc/ChangeLog.txt
index b7524039..3f32f0bc 100644
--- a/doc/ChangeLog.txt
+++ b/doc/ChangeLog.txt
@@ -11,6 +11,9 @@ The Cudd BBD packager is now required.
 
 The USE_TCL_READLINE option defaults to ON.
 
+The variable link_make_black_boxes has been removed.
+Use the -no_black_boxes option to the link_design command.
+
 Release 2.5.0 2024/01/17
 -------------------------
 
diff --git a/doc/OpenSTA.odt b/doc/OpenSTA.odt
index bf5937f5..f84e59d4 100644
Binary files a/doc/OpenSTA.odt and b/doc/OpenSTA.odt differ
diff --git a/doc/OpenSTA.pdf b/doc/OpenSTA.pdf
index 655f1682..26031ffc 100644
Binary files a/doc/OpenSTA.pdf and b/doc/OpenSTA.pdf differ
diff --git a/include/sta/Sta.hh b/include/sta/Sta.hh
index be39820b..52c2ef2d 100644
--- a/include/sta/Sta.hh
+++ b/include/sta/Sta.hh
@@ -116,9 +116,8 @@ public:
   // linked network.
   void readNetlistBefore();
   // Return true if successful.
-  bool linkDesign(const char *top_cell_name);
-  bool linkMakeBlackBoxes() const;
-  void setLinkMakeBlackBoxes(bool make);
+  bool linkDesign(const char *top_cell_name,
+                  bool make_black_boxes);
 
   // SDC Swig API.
   Instance *currentInstance() const;
@@ -1452,7 +1451,6 @@ protected:
   ReportPath *report_path_;
   Power *power_;
   Tcl_Interp *tcl_interp_;
-  bool link_make_black_boxes_;
   bool update_genclks_;
   EquivCells *equiv_cells_;
   bool graph_sdc_annotated_;
diff --git a/network/Network.i b/network/Network.i
index 0953300e..8ccc7a7a 100644
--- a/network/Network.i
+++ b/network/Network.i
@@ -253,21 +253,10 @@ set_cmd_namespace_cmd(const char *namespc)
 }
 
 bool
-link_design_cmd(const char *top_cell_name)
+link_design_cmd(const char *top_cell_name,
+                bool make_black_boxes)
 {
-  return Sta::sta()->linkDesign(top_cell_name);
-}
-
-bool
-link_make_black_boxes()
-{
-  return Sta::sta()->linkMakeBlackBoxes();
-}
-
-void
-set_link_make_black_boxes(bool make)
-{
-  Sta::sta()->setLinkMakeBlackBoxes(make);
+  return Sta::sta()->linkDesign(top_cell_name, make_black_boxes);
 }
 
 Instance *
diff --git a/search/Sta.cc b/search/Sta.cc
index 79325f65..06a7429f 100644
--- a/search/Sta.cc
+++ b/search/Sta.cc
@@ -268,7 +268,6 @@ Sta::Sta() :
   clk_skews_(nullptr),
   report_path_(nullptr),
   power_(nullptr),
-  link_make_black_boxes_(true),
   update_genclks_(false),
   equiv_cells_(nullptr),
   graph_sdc_annotated_(false),
@@ -735,29 +734,18 @@ Sta::readNetlistBefore()
 }
 
 bool
-Sta::linkDesign(const char *top_cell_name)
+Sta::linkDesign(const char *top_cell_name,
+                bool make_black_boxes)
 {
   clear();
   Stats stats(debug_, report_);
   bool status = network_->linkNetwork(top_cell_name,
-				      link_make_black_boxes_,
+				      make_black_boxes,
 				      report_);
   stats.report("Link");
   return status;
 }
 
-bool
-Sta::linkMakeBlackBoxes() const
-{
-  return link_make_black_boxes_;
-}
-
-void
-Sta::setLinkMakeBlackBoxes(bool make)
-{
-  link_make_black_boxes_ = make;
-}
-
 ////////////////////////////////////////////////////////////////
 
 void
diff --git a/tcl/Link.tcl b/tcl/Link.tcl
index 39912ddf..a278c710 100644
--- a/tcl/Link.tcl
+++ b/tcl/Link.tcl
@@ -18,11 +18,13 @@
 
 namespace eval sta {
 
-define_cmd_args "link_design" {[top_cell_name]}
+define_cmd_args "link_design" {[-no_black_boxes]\
+                                 [top_cell_name]}
 
 proc_redirect link_design {
   variable current_design_name
 
+  parse_key_args "link_design" args keys {} flags {-no_black_boxes}
   check_argc_eq0or1 "link_design" $args
   if { $args == "" } {
     set top_cell_name ""
@@ -37,7 +39,11 @@ proc_redirect link_design {
       set top_cell_name $current_design_name
     }
   }
-  link_design_cmd $top_cell_name
+  set make_black_boxes 1
+  if { [info exists flags(-no_black_boxes)] } {
+    set make_black_boxes 0
+  }
+  link_design_cmd $top_cell_name $make_black_boxes
 }
 
 # sta namespace end
diff --git a/tcl/Variables.tcl b/tcl/Variables.tcl
index 0d054dbf..01e45d0e 100644
--- a/tcl/Variables.tcl
+++ b/tcl/Variables.tcl
@@ -22,14 +22,6 @@ namespace eval sta {
 #
 ################################################################
 
-trace variable ::link_make_black_boxes "rw" \
-  sta::trace_link_make_black_boxes
-
-proc trace_link_make_black_boxes { name1 name2 op } {
-  trace_boolean_var $op ::link_make_black_boxes \
-    link_make_black_boxes set_link_make_black_boxes
-}
-
 # Default digits to print after decimal point for reporting commands.
 set ::sta_report_default_digits 2