diff --git a/gtsam/discrete/Signature.cpp b/gtsam/discrete/Signature.cpp
index 94b160a29..361fc0b0a 100644
--- a/gtsam/discrete/Signature.cpp
+++ b/gtsam/discrete/Signature.cpp
@@ -38,19 +38,7 @@ namespace gtsam {
     using boost::phoenix::push_back;
 
     // Special rows, true and false
-    Signature::Row createF() {
-      Signature::Row r(2);
-      r[0] = 1;
-      r[1] = 0;
-      return r;
-    }
-    Signature::Row createT() {
-      Signature::Row r(2);
-      r[0] = 0;
-      r[1] = 1;
-      return r;
-    }
-    Signature::Row T = createT(), F = createF();
+    Signature::Row F{1, 0}, T{0, 1};  
 
     // Special tables (inefficient, but do we care for user input?)
     Signature::Table logic(bool ff, bool ft, bool tf, bool tt) {
@@ -69,40 +57,13 @@ namespace gtsam {
         table = or_ | and_ | rows;
         or_ = qi::lit("OR")[qi::_val = logic(false, true, true, true)];
         and_ = qi::lit("AND")[qi::_val = logic(false, false, false, true)];
-        rows = +(row | true_ | false_); // only loads first of the rows under boost 1.42
+        rows = +(row | true_ | false_);
         row = qi::double_ >> +("/" >> qi::double_);
         true_ = qi::lit("T")[qi::_val = T];
         false_ = qi::lit("F")[qi::_val = F];
       }
     } grammar;
 
-    // Create simpler parsing function to avoid the issue of only parsing a single row
-    bool parse_table(const string& spec, Signature::Table& table) {
-      // check for OR, AND on whole phrase
-      It f = spec.begin(), l = spec.end();
-      if (qi::parse(f, l,
-            qi::lit("OR")[ph::ref(table) = logic(false, true, true, true)]) ||
-          qi::parse(f, l,
-            qi::lit("AND")[ph::ref(table) = logic(false, false, false, true)]))
-        return true;
-
-      // tokenize into separate rows
-      istringstream iss(spec);
-      string token;
-      while (iss >> token) {
-        Signature::Row values;
-        It tf = token.begin(), tl = token.end();
-        bool r = qi::parse(tf, tl,
-            qi::double_[push_back(ph::ref(values), qi::_1)] >> +("/" >> qi::double_[push_back(ph::ref(values), qi::_1)]) |
-            qi::lit("T")[ph::ref(values) = T] |
-            qi::lit("F")[ph::ref(values) = F] );
-        if (!r)
-          return false;
-        table.push_back(values);
-      }
-
-      return true;
-    }
   } // \namespace parser
 
   ostream& operator <<(ostream &os, const Signature::Row &row) {
@@ -166,14 +127,11 @@ namespace gtsam {
   Signature& Signature::operator=(const string& spec) {
     spec_.reset(spec);
     Table table;
-    // NOTE: using simpler parse function to ensure boost back compatibility
-//    parser::It f = spec.begin(), l = spec.end();
-    bool success = //
-//        qi::phrase_parse(f, l, parser::grammar.table, qi::space, table); // using full grammar
-          parser::parse_table(spec, table);
+    parser::It f = spec.begin(), l = spec.end();
+    bool success =
+        qi::phrase_parse(f, l, parser::grammar.table, qi::space, table);
     if (success) {
-      for(Row& row: table)
-        normalize(row);
+      for (Row& row : table) normalize(row);
       table_.reset(table);
     }
     return *this;
diff --git a/gtsam/discrete/Signature.h b/gtsam/discrete/Signature.h
index 6c59b5bff..2a8248171 100644
--- a/gtsam/discrete/Signature.h
+++ b/gtsam/discrete/Signature.h
@@ -103,7 +103,7 @@ namespace gtsam {
     /** Add a parent */
     Signature& operator,(const DiscreteKey& parent);
 
-    /** Add the CPT spec - Fails in boost 1.40 */
+    /** Add the CPT spec */
     Signature& operator=(const std::string& spec);
 
     /** Add the CPT spec directly as a table */
@@ -122,7 +122,6 @@ namespace gtsam {
   /**
    * Helper function to create Signature objects
    * example: Signature s(D % "99/1");
-   * Uses string parser, which requires BOOST 1.42 or higher
    */
   GTSAM_EXPORT Signature operator%(const DiscreteKey& key, const std::string& parent);