diff --git a/src/hdf5_usecases/CMakeLists.txt b/src/hdf5_usecases/CMakeLists.txt
index 4cf2639558..d650716aa8 100644
--- a/src/hdf5_usecases/CMakeLists.txt
+++ b/src/hdf5_usecases/CMakeLists.txt
@@ -18,7 +18,7 @@
 ################################################################################
 
 ADD_EXECUTABLE(hdf5_federate federate.cpp)
-TARGET_LINK_LIBRARIES(hdf5_federate IfcParse)
+TARGET_LINK_LIBRARIES(hdf5_federate IfcParse ${ICU_LIBRARIES} ${Boost_LIBRARIES})
 
 ADD_EXECUTABLE(hdf5_lod lod.cpp)
-TARGET_LINK_LIBRARIES(hdf5_lod IfcParse IfcGeom)
+TARGET_LINK_LIBRARIES(hdf5_lod IfcParse IfcGeom ${OPENCASCADE_LIBRARIES} ${Boost_LIBRARIES} ${ICU_LIBRARIES})
diff --git a/src/hdf5_usecases/lod.cpp b/src/hdf5_usecases/lod.cpp
index d47da290d2..a28eaf2eac 100644
--- a/src/hdf5_usecases/lod.cpp
+++ b/src/hdf5_usecases/lod.cpp
@@ -19,21 +19,113 @@
 
 #include "../../../src/ifcparse/IfcHdf5File.h"
 #include "../../../src/ifcgeom/IfcGeom.h"
+#include "../../../src/ifcparse/IfcWritableEntity.h"
 
 #include <Bnd_Box.hxx>
 #include <BRepBndLib.hxx>
 
+#include <algorithm>
+
+#include "multifile_instance_locator.h"
+
 int main(int, char** argv) {
 	IfcParse::IfcFile f;
 	f.Init(argv[1]);
 
-	std::vector<IfcSchema::IfcProductDefinitionShape*> new_defs;
-	IfcSchema::IfcProductDefinitionShape::list::ptr defs = f.entitiesByType<IfcSchema::IfcProductDefinitionShape>();
+	IfcSchema::IfcProductDefinitionShape::list::ptr defs_ = f.entitiesByType<IfcSchema::IfcProductDefinitionShape>();
+	std::vector<IfcSchema::IfcProductDefinitionShape*> defs(defs_->begin(), defs_->end());
+	// Make sure to sort by id to have new definitions lining up in the same order
+	std::sort(defs.begin(), defs.end(), [](IfcSchema::IfcProductDefinitionShape* a, IfcSchema::IfcProductDefinitionShape* b) {
+		return a->data().id() < b->data().id();
+	});
+
+	IfcSchema::IfcStyledItem::list::ptr styles = f.entitiesByType<IfcSchema::IfcStyledItem>();
 
 	IfcGeom::Kernel kernel;
 	kernel.initializeUnits(*f.entitiesByType<IfcSchema::IfcUnitAssignment>()->begin());
 
-	std::transform(defs->begin(), defs->end(), std::back_inserter(new_defs), [&kernel](IfcSchema::IfcProductDefinitionShape* def) {
+	std::set<IfcSchema::Type::Enum> geometric_types{ IfcSchema::Type::IfcStyledItem };
+	std::set<IfcSchema::Type::Enum> other_types;
+
+	std::set<IfcUtil::IfcBaseClass*> geometric_instances;
+
+	std::for_each(styles->begin(), styles->end(), [&geometric_instances](IfcSchema::IfcStyledItem* style) {
+		geometric_instances.insert(style);
+	});
+
+	int N = defs.size();
+	int n = 0;
+
+	std::for_each(defs.begin(), defs.end(), [&f, &geometric_types, &geometric_instances, N, &n](IfcSchema::IfcProductDefinitionShape* def) {
+		auto refs = f.traverse(def);
+		geometric_instances.insert(refs->begin(), refs->end());
+		std::for_each(refs->begin(), refs->end(), [&geometric_types](IfcUtil::IfcBaseClass* inst) {
+			geometric_types.insert(inst->declaration().type());
+		});
+		if (n++ % 1000 == 0) {
+			std::cerr << "\r" << n * 100 / N << std::flush;
+		}
+	});
+
+	std::function<void(IfcUtil::IfcBaseClass*, IfcUtil::IfcBaseClass*)> fn;
+	fn = [&f, &geometric_instances, &other_types, &fn](IfcUtil::IfcBaseClass* root, IfcUtil::IfcBaseClass* inst) {
+		if (geometric_instances.find(inst) == geometric_instances.end()) {
+			if (inst->declaration().type() == IfcSchema::Type::IfcCircle) {
+				std::cerr << "circle reached by " << root->data().toString() << std::endl;
+			}
+			other_types.insert(inst->declaration().type());
+			auto refs = f.traverse(inst, 1);
+			std::for_each(refs->begin() + 1, refs->end(), [&fn, root](IfcUtil::IfcBaseClass* inst) {
+				fn(root, inst);
+			});
+		}
+	};
+
+	N = std::distance(f.begin(), f.end());
+	n = 0;
+
+	std::for_each(f.begin(), f.end(), [&fn, N, &n](const auto& pair) {
+		fn(pair.second, pair.second);
+		if (n++ % 1000 == 0) {
+			std::cerr << "\r" << n * 100 / N << std::flush;
+		}
+	});
+
+	std::set<IfcSchema::Type::Enum> only_geometric;
+	std::set_difference(geometric_types.begin(), geometric_types.end(), 
+		other_types.begin(), other_types.end(), 
+		std::inserter(only_geometric, only_geometric.begin()));
+
+	for (auto ty : only_geometric) {
+		std::cerr << IfcSchema::Type::ToString(ty) << std::endl;
+	}
+
+	std::cin.get();
+
+	// IfcSchema::Type::IfcAxis2Placement3D,IfcSchema::Type::IfcCartesianPoint,IfcSchema::Type::IfcDirection,IfcSchema::Type::IfcGeometricRepresentationSubContext
+		
+	std::vector<IfcUtil::IfcBaseClass*> new_defs, old_defs, old_geom_defs, all_old_defs;
+
+	std::for_each(only_geometric.begin(), only_geometric.end(), [&f, &old_geom_defs](IfcSchema::Type::Enum t) {
+		auto insts = f.entitiesByType(t);
+		std::for_each(insts->begin(), insts->end(), [t, &old_geom_defs](IfcUtil::IfcBaseClass* inst) {
+			if (inst->declaration().type() == t) {
+				old_geom_defs.push_back(inst);
+			}
+		});
+	});
+
+	std::for_each(f.begin(), f.end(), [&fn, &only_geometric, &old_defs](const auto& pair) {
+		IfcUtil::IfcBaseClass* inst = pair.second;
+		auto ty = inst->declaration().type();
+		if (only_geometric.find(ty) == only_geometric.end()) {
+			old_defs.push_back(inst);
+		}
+	});
+
+	auto id = f.FreshId();
+
+	std::for_each(defs.begin(), defs.end(), [&kernel, &id, &old_defs, &new_defs](IfcSchema::IfcProductDefinitionShape* def) {
 		Bnd_Box box;
 		auto reps = def->Representations();
 		IfcSchema::IfcRepresentationContext* context;
@@ -64,6 +156,59 @@ int main(int, char** argv) {
 		new_reps->push(rep);
 		
 		IfcSchema::IfcProductDefinitionShape* new_def = new IfcSchema::IfcProductDefinitionShape(boost::none, boost::none, new_reps);
+		
+		new_def->data().isWritable()->setId(id++);
+
+		// NB: Corner is added to existing definitions
+		old_defs.push_back(corner);
+		new_defs.push_back(bbox);
+		new_defs.push_back(rep);
+		new_defs.push_back(new_def);
+
 		return new_def;
 	});
+
+	H5::H5File hdf(argv[1] + std::string(".hdf"), H5F_ACC_TRUNC);
+	
+	H5::Group population = hdf.createGroup("population");
+	H5::Group low = hdf.createGroup("low");
+	H5::Group hi = hdf.createGroup("hi");
+	
+	auto iden = [](IfcUtil::IfcBaseClass* inst) { return inst; };
+
+	std::set<IfcSchema::Type::Enum> old_new_geom_types;
+
+	std::vector<std::vector<IfcUtil::IfcBaseClass*>*> all_vectors = std::vector<std::vector<IfcUtil::IfcBaseClass*>*>{ &new_defs, &old_defs, &old_geom_defs };
+	for (auto vec_ : all_vectors) {
+		auto& vec = *vec_;
+		for (auto& inst : vec) {
+			old_new_geom_types.insert(inst->declaration().type());
+		}
+	}
+
+	all_old_defs.insert(all_old_defs.end(), old_defs.begin(), old_defs.end());
+	all_old_defs.insert(all_old_defs.end(), old_geom_defs.begin(), old_geom_defs.end());
+
+	if (std::distance(all_old_defs.begin(), all_old_defs.end()) != std::distance(f.begin(), f.end())) {
+		std::cerr << "Missign instances";
+		abort();
+	}
+
+	multifile_instance_locator* locator = new multifile_instance_locator(
+		old_new_geom_types.begin(), old_new_geom_types.end(),
+		all_old_defs.begin(), all_old_defs.end());
+
+	IfcParse::Hdf5Settings settings;
+	// settings.profile() = IfcParse::Hdf5Settings::standard_referenced;
+
+	IfcParse::IfcHdf5File ifc_hdf5(hdf, get_schema(), settings);
+	ifc_hdf5.write_schema();
+	
+	IfcParse::IfcSpfHeader header;
+	header.set_default();
+
+	{
+		IfcParse::instance_enumerator enumerator(&f.header(), old_defs.begin(), old_defs.end());
+		ifc_hdf5.write_population(population, enumerator, locator);
+	}	
 }
\ No newline at end of file
diff --git a/src/hdf5_usecases/multifile_instance_locator.h b/src/hdf5_usecases/multifile_instance_locator.h
index 50c39370c4..dc9b6c359a 100644
--- a/src/hdf5_usecases/multifile_instance_locator.h
+++ b/src/hdf5_usecases/multifile_instance_locator.h
@@ -27,16 +27,17 @@ public:
 	typedef std::vector<IfcUtil::IfcBaseClass*>::const_iterator full_const_iterator;
 	
 private:
-	H5::H5File& root_file_;
+	H5::H5File* root_file_;
 
 	mapping_t mapping_;
 	std::set<IfcUtil::IfcBaseClass*> initial_population_set_;
+	std::set<IfcSchema::Type::Enum> initial_types_included_set_;
 
 	population_t initial_population_;
 	population_t subsequent_population_;
 	std::vector<IfcUtil::IfcBaseClass*> subsequent_minus_initial_;
 
-	H5::Group& initial_group_;
+	H5::Group* initial_group_;
 	H5::Group* subsequent_group_;
 	H5::H5File* subsequent_file_;
 	std::string root_;
@@ -45,9 +46,9 @@ public:
 
 	template <typename ForwardIterator>
 	multifile_instance_locator(H5::H5File& root_file, H5::Group& group, mapping_t mapping, ForwardIterator b, ForwardIterator e)
-		: root_file_(root_file)
+		: root_file_(&root_file)
 		, mapping_(mapping)
-		, initial_group_(group)
+		, initial_group_(&group)
 		, subsequent_group_(nullptr)
 	{
 		initial_population_set_.insert(b, e);
@@ -80,6 +81,28 @@ public:
 		});
 	}
 
+	template <typename ForwardIteratorTypes, typename ForwardIteratorInsts>
+	multifile_instance_locator(ForwardIteratorTypes types_all_begin, ForwardIteratorTypes types_all_end, ForwardIteratorInsts insts_begin, ForwardIteratorInsts insts_end) {
+		initial_population_.first.assign(types_all_begin, types_all_end);
+		std::sort(initial_population_.first.begin(), initial_population_.first.end());
+
+		std::for_each(this->begin(), this->end(), [this, &insts_begin, &insts_end](IfcSchema::Type::Enum t) {
+			std::vector<IfcUtil::IfcBaseEntity*> by_type;
+
+			std::for_each(insts_begin, insts_end, [t, &by_type](IfcUtil::IfcBaseClass* inst) {
+				if (inst->declaration().type() == t && inst->declaration().as_entity()) {
+					by_type.push_back((IfcUtil::IfcBaseEntity*) inst);
+				}
+			});
+
+			std::sort(by_type.begin(), by_type.end(), [](IfcUtil::IfcBaseEntity* i1, IfcUtil::IfcBaseEntity* i2) {
+				return i1->data().id() < i2->data().id();
+			});
+
+			initial_population_.second.emplace_back(by_type);
+		});
+	}
+
 	const_iterator begin() const {
 		if (subsequent_group_) {
 			return subsequent_population_.first.begin();
@@ -126,7 +149,7 @@ public:
 				
 		if (initial_population_set_.find(v) != initial_population_set_.end()) {
 			pop = &initial_population_;
-			group = &initial_group_;
+			group = initial_group_;
 			current_root = boost::none;
 		} else {
 			pop = &subsequent_population_;
@@ -148,7 +171,7 @@ public:
 
 		std::string full_path = group->getObjName() + "/" + path + "_instances";
 
-		root_file_.reference(ptr, full_path, space);
+		root_file_->reference(ptr, full_path, space);
 		ptr = static_cast<uint8_t*>(ptr) + sizeof(hdset_reg_ref_t);
 	}