diff --git a/CMakeLists.txt b/CMakeLists.txt
index 961a6ab9..b38873ad 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -98,7 +98,6 @@ set(STA_SOURCE
   liberty/TableModel.cc
   liberty/TimingArc.cc
   liberty/TimingRole.cc
-  liberty/Transition.cc
   liberty/Units.cc
   liberty/Wireload.cc
   
@@ -135,7 +134,6 @@ set(STA_SOURCE
   sdc/PinPair.cc
   sdc/PortDelay.cc
   sdc/PortExtCap.cc
-  sdc/RiseFallMinMax.cc
   sdc/RiseFallValues.cc
   sdc/Sdc.cc
   sdc/SdcGraph.cc
@@ -202,11 +200,13 @@ set(STA_SOURCE
   util/Report.cc
   util/ReportStd.cc
   util/ReportTcl.cc
+  util/RiseFallMinMax.cc
   util/Stats.cc
   util/StringSeq.cc
   util/StringSet.cc
   util/StringUtil.cc
   util/TokenParser.cc
+  util/Transition.cc
   
   verilog/VerilogReader.cc
   verilog/VerilogWriter.cc
diff --git a/include/sta/MinMax.hh b/include/sta/MinMax.hh
index f4543f34..ae0ebb79 100644
--- a/include/sta/MinMax.hh
+++ b/include/sta/MinMax.hh
@@ -126,23 +126,4 @@ private:
   static MinMaxAll all_;
 };
 
-////////////////////////////////////////////////////////////////
-
-// Obsolete. Use range iteration.
-class MinMaxIterator : public Iterator<MinMax*>
-{
-public:
-  MinMaxIterator() : index_(0), index_max_(MinMax::index_max) {}
-  explicit MinMaxIterator(const MinMaxAll *min_max);
-  bool hasNext() { return index_ <= index_max_; }
-  MinMax *next()
-  { return (index_++ == 0) ? MinMax::min() : MinMax::max(); }
-
-private:
-  int index_;
-  int index_max_;
-};
-
-typedef MinMaxIterator EarlyLateIterator;
-
 } // namespace
diff --git a/include/sta/Transition.hh b/include/sta/Transition.hh
index 164fe3b0..2df81d8e 100644
--- a/include/sta/Transition.hh
+++ b/include/sta/Transition.hh
@@ -191,20 +191,4 @@ private:
   static int max_index_;
 };
 
-// Obsolete. Use range iteration instead.
-// for (RiseFall *rf : RiseFall::range()) {}
-class RiseFallIterator : public Iterator<RiseFall*>
-{
-public:
-  RiseFallIterator() : index_(0), index_max_(RiseFall::index_max) {}
-  explicit RiseFallIterator(const RiseFallBoth *rf);
-  void init();
-  virtual bool hasNext();
-  virtual RiseFall *next();
-
-private:
-  int index_;
-  int index_max_;
-};
-
 } // namespace
diff --git a/util/MinMax.cc b/util/MinMax.cc
index ecb297d3..b4b912d1 100644
--- a/util/MinMax.cc
+++ b/util/MinMax.cc
@@ -171,18 +171,4 @@ MinMaxAll::find(const char *min_max)
     return nullptr;
 }
 
-////////////////////////////////////////////////////////////////
-
-MinMaxIterator::MinMaxIterator(const MinMaxAll *min_max)
-{
-  if (min_max == MinMaxAll::all()) {
-    index_ = 0;
-    index_max_ = MinMax::index_max;
-  }
-  else {
-    index_ = min_max->asMinMax()->index();
-    index_max_ = index_;
-  }
-}
-
 } // namespace
diff --git a/sdc/RiseFallMinMax.cc b/util/RiseFallMinMax.cc
similarity index 100%
rename from sdc/RiseFallMinMax.cc
rename to util/RiseFallMinMax.cc
diff --git a/liberty/Transition.cc b/util/Transition.cc
similarity index 83%
rename from liberty/Transition.cc
rename to util/Transition.cc
index 5da7aa13..88fe4b73 100644
--- a/liberty/Transition.cc
+++ b/util/Transition.cc
@@ -105,26 +105,26 @@ RiseFall::asTransition() const
 ////////////////////////////////////////////////////////////////
 
 RiseFallBoth RiseFallBoth::rise_("rise", "^", 0,
-					   RiseFall::rise(),
-					   {RiseFall::rise()},
-					   {RiseFall::riseIndex()});
+                                 RiseFall::rise(),
+                                 {RiseFall::rise()},
+                                 {RiseFall::riseIndex()});
 RiseFallBoth RiseFallBoth::fall_("fall", "v", 1,
-					   RiseFall::fall(),
-					   {RiseFall::fall()},
-					   {RiseFall::fallIndex()});
+                                 RiseFall::fall(),
+                                 {RiseFall::fall()},
+                                 {RiseFall::fallIndex()});
 RiseFallBoth RiseFallBoth::rise_fall_("rise_fall", "rf", 2,
-						nullptr,
-						{RiseFall::rise(),
-						 RiseFall::fall()},
-						{RiseFall::riseIndex(),
-						 RiseFall::fallIndex()});
+                                      nullptr,
+                                      {RiseFall::rise(),
+                                       RiseFall::fall()},
+                                      {RiseFall::riseIndex(),
+                                       RiseFall::fallIndex()});
 
 RiseFallBoth::RiseFallBoth(const char *name,
-				     const char *short_name,
-				     int sdf_triple_index,
-				     RiseFall *as_rise_fall,
-				     std::vector<RiseFall*> range,
-				     std::vector<int> range_index) :
+                           const char *short_name,
+                           int sdf_triple_index,
+                           RiseFall *as_rise_fall,
+                           std::vector<RiseFall*> range,
+                           std::vector<int> range_index) :
   name_(name),
   short_name_(stringCopy(short_name)),
   sdf_triple_index_(sdf_triple_index),
@@ -240,37 +240,4 @@ Transition::setName(const char *name)
   name_ = stringCopy(name);
 }
 
-////////////////////////////////////////////////////////////////
-
-RiseFallIterator::RiseFallIterator(const RiseFallBoth *rf)
-{
-  if (rf == RiseFallBoth::riseFall()) {
-    index_ = 0;
-    index_max_ = RiseFall::index_max;
-  }
-  else {
-    index_ = rf->asRiseFall()->index();
-    index_max_ = index_;
-  }
-}
-
-void
-RiseFallIterator::init()
-{
-  index_ = 0;
-  index_max_ = RiseFall::index_max;
-}
-
-bool
-RiseFallIterator::hasNext()
-{
-  return index_ <= index_max_;
-}
-
-RiseFall *
-RiseFallIterator::next()
-{
-  return (index_++ == 0) ? RiseFall::rise() : RiseFall::fall();
-}
-
 } // namespace