diff --git a/bigdata-core/bigdata-rdf/src/java/com/bigdata/rdf/sparql/ast/optimizers/AbstractJoinGroupOptimizer.java b/bigdata-core/bigdata-rdf/src/java/com/bigdata/rdf/sparql/ast/optimizers/AbstractJoinGroupOptimizer.java
index 52a5d42d61..f9e40d38ac 100644
--- a/bigdata-core/bigdata-rdf/src/java/com/bigdata/rdf/sparql/ast/optimizers/AbstractJoinGroupOptimizer.java
+++ b/bigdata-core/bigdata-rdf/src/java/com/bigdata/rdf/sparql/ast/optimizers/AbstractJoinGroupOptimizer.java
@@ -33,6 +33,7 @@
 import com.bigdata.bop.IBindingSet;
 import com.bigdata.bop.bindingSet.ListBindingSet;
 import com.bigdata.rdf.sparql.ast.ArbitraryLengthPathNode;
+import com.bigdata.rdf.sparql.ast.AssignmentNode;
 import com.bigdata.rdf.sparql.ast.ConstantNode;
 import com.bigdata.rdf.sparql.ast.FilterNode;
 import com.bigdata.rdf.sparql.ast.GraphPatternGroup;
@@ -250,6 +251,16 @@ private void optimize(final AST2BOpContext ctx,
 
                 optimize(ctx, sa, bSets, childGroup);
             	
+            } else if (child instanceof AssignmentNode) {
+                // This optimize execution is needed to process expression value,
+                // for example, property paths inside EXISTS
+                // Ref: Test_Ticket_T173243
+                final AssignmentNode assignmentNode = (AssignmentNode) child;
+
+                final IValueExpressionNode valueExpressionNode = assignmentNode.getValueExpressionNode();
+
+                optimize(ctx, sa, bSets, valueExpressionNode);
+
             }
             
         }
diff --git a/bigdata-sails-test/src/test/java/com/bigdata/rdf/sail/webapp/Test_Ticket_T173243.java b/bigdata-sails-test/src/test/java/com/bigdata/rdf/sail/webapp/Test_Ticket_T173243.java
new file mode 100644
index 0000000000..951d7d370e
--- /dev/null
+++ b/bigdata-sails-test/src/test/java/com/bigdata/rdf/sail/webapp/Test_Ticket_T173243.java
@@ -0,0 +1,114 @@
+/*
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; version 2 of the License.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+
+package com.bigdata.rdf.sail.webapp;
+
+import junit.framework.Test;
+
+import java.util.Arrays;
+
+import org.openrdf.model.Statement;
+import org.openrdf.model.URI;
+import org.openrdf.model.impl.URIImpl;
+import org.openrdf.model.impl.ValueFactoryImpl;
+import org.openrdf.query.QueryLanguage;
+import org.openrdf.query.TupleQuery;
+import org.openrdf.query.TupleQueryResult;
+
+import com.bigdata.journal.IIndexManager;
+import com.bigdata.rdf.sail.webapp.client.RemoteRepository.AddOp;
+import com.bigdata.rdf.sail.webapp.client.RemoteRepository.RemoveOp;
+
+/**
+ * UnsupportedOperationException on property path in EXISTS.
+ * @See https://phabricator.wikimedia.org/T173243
+ * 
+ */
+public class Test_Ticket_T173243<S extends IIndexManager> extends
+		AbstractTestNanoSparqlClient<S> {
+
+	public Test_Ticket_T173243() {
+
+	}
+
+	public Test_Ticket_T173243(final String name) {
+
+		super(name);
+
+	}
+
+	public static Test suite() {
+
+		return ProxySuiteHelper.suiteWhenStandalone(Test_Ticket_T173243.class,
+                "test.*", TestMode.triples
+                );
+       
+	}
+
+    /**
+    * Test supposed to check if constants .. will be resolved
+     * @throws Exception 
+    */
+    public void test_propertyPathsInExists_T173243() throws Exception {
+//        @Test
+//        public void propertyPathsInExists_T173243() {
+//            // UnsupportedOperationException on property path in EXISTS
+//            // https://phabricator.wikimedia.org/T173243
+//            addSimpleLabels("Q173243");
+//            StringBuilder query = uris().prefixes(Ontology.prefix(new StringBuilder()));
+//            query.append("SELECT * { BIND(EXISTS { ?a p:1/p:2 ?b. } AS ?t) }");
+//            assertLabelQueryResult(query.toString(),
+//                binds("pLabel", Literal.class)
+//            );
+//        }
+
+        // Clear DB per task description (Executing the query over the empty database)
+        m_repo.remove(new RemoveOp(null, null, null));
+
+        final URI s = new URIImpl("t:Q173243");
+        final URI s1 = new URIImpl("t:Q173243PP1");
+        final URI s2 = new URIImpl("t:Q173243PP2");
+        final URI p1 = new URIImpl("t:P1");
+        final URI p2 = new URIImpl("t:P2");
+
+        ValueFactoryImpl vf = ValueFactoryImpl.getInstance();
+        final Statement[] a = new Statement[] { 
+                vf.createStatement(s, p1, s1),
+                vf.createStatement(s1, p2, s2)
+                };
+
+        final AddOp addOp = new AddOp(Arrays.asList(a));
+
+        m_repo.add(addOp);
+        String query = "SELECT * WHERE { BIND(EXISTS{ ?a <t:P1>/<t:P2> ?b . } AS ?t) }";
+        final TupleQuery tq = m_repo.getBigdataSailRemoteRepository().getConnection().prepareTupleQuery(QueryLanguage.SPARQL, query, null);
+        final TupleQueryResult tqr = tq.evaluate();
+        try {
+            int count = 0;
+            while (tqr.hasNext()) {
+                System.out.println(tqr.next());
+                count++;
+            }
+            assertEquals(1,count); // asserting successful execution of the query, as it was failing while parsing
+        } catch (Exception e) {
+            log.info("Error while evaluating " + tq, e);
+            throw e;
+        } finally {
+            tqr.close();
+        }
+    }
+
+}