diff --git a/CMakeLists.txt b/CMakeLists.txt
index 106465e95..5d5a9969d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -338,7 +338,7 @@ else()
     set(GNSSSDR_GTEST_LOCAL_VERSION "1.12.1")
 endif()
 set(GNSSSDR_GNSS_SIM_LOCAL_VERSION "master")
-set(GNSSSDR_GNSSTK_LOCAL_VERSION "12.1.0")
+set(GNSSSDR_GNSSTK_LOCAL_VERSION "13.4.0")
 set(GNSSSDR_MATIO_LOCAL_VERSION "1.5.23")
 set(GNSSSDR_PUGIXML_LOCAL_VERSION "1.12")
 set(GNSSSDR_PROTOCOLBUFFERS_LOCAL_VERSION "21.1")
diff --git a/cmake/Modules/FindGNSSTK.cmake b/cmake/Modules/FindGNSSTK.cmake
index b1b1d9076..121e48477 100644
--- a/cmake/Modules/FindGNSSTK.cmake
+++ b/cmake/Modules/FindGNSSTK.cmake
@@ -83,10 +83,16 @@ if(GNSSTK_LIBRARY AND GNSSTK_INCLUDE_DIR)
 endif()
 
 if(GNSSTK_VERSION)
-    if(GNSSTK_VERSION VERSION_GREATER ${GNSSSDR_GNSSTK_LOCAL_VERSION})
-        unset(GNSSTK_LIBRARY CACHE)
-        unset(GNSSTK_INCLUDE_DIR CACHE)
+    if(GNSSTK_VERSION VERSION_LESS "9.0.0")
+        set(GNSSTK_OLDER_THAN_9 TRUE)
     endif()
+    if(GNSSTK_VERSION VERSION_LESS "13.0.0")
+        set(GNSSTK_OLDER_THAN_13 TRUE)
+    endif()
+endif()
+
+if(NOT EXISTS ${GNSSTK_INCLUDE_DIR}/gnsstk/GPSEphemerisStore.hpp)
+    set(GNSSTK_OLDER_THAN_13 TRUE)
 endif()
 
 # handle the QUIET and REQUIRED arguments and set GNSSTK_FOUND to TRUE if
@@ -136,4 +142,6 @@ mark_as_advanced(GNSSTK_LIBRARY
     GNSSTK_INCLUDE_DIR
     GNSSTK_USES_GPSTK_NAMESPACE
     GNSSTK_OLDER_THAN_8
+    GNSSTK_OLDER_THAN_9
+    GNSSTK_OLDER_THAN_13
 )
diff --git a/src/tests/CMakeLists.txt b/src/tests/CMakeLists.txt
index 341b30b9f..cebfd2305 100644
--- a/src/tests/CMakeLists.txt
+++ b/src/tests/CMakeLists.txt
@@ -359,7 +359,7 @@ if(ENABLE_UNIT_TESTING_EXTRA OR ENABLE_SYSTEM_TESTING_EXTRA OR ENABLE_FPGA)
         endif()
         set(GNSSTK_PATCH_COMMAND
             cd ${CMAKE_BINARY_DIR}/thirdparty/gnsstk-${GNSSSDR_GNSSTK_LOCAL_VERSION} &&
-            ${Patch_EXECUTABLE} ${CMAKE_BINARY_DIR}/thirdparty/gnsstk-${GNSSSDR_GNSSTK_LOCAL_VERSION}/CMakeLists.txt < ${CMAKE_SOURCE_DIR}/src/tests/data/gnsstk_static.patch
+            ${Patch_EXECUTABLE} ${CMAKE_BINARY_DIR}/thirdparty/gnsstk-${GNSSSDR_GNSSTK_LOCAL_VERSION}/CMakeLists.txt < ${CMAKE_SOURCE_DIR}/src/tests/data/gnsstk_static13.patch
         )
         # Patch only once
         if(EXISTS ${CMAKE_BINARY_DIR}/thirdparty/gnsstk-${GNSSSDR_GNSSTK_LOCAL_VERSION}/CMakeLists.txt)
@@ -561,6 +561,9 @@ if(ENABLE_UNIT_TESTING)
         if(GNSSTK_USES_GPSTK_NAMESPACE)
             target_compile_definitions(run_tests PRIVATE -DGNSSTK_USES_GPSTK_NAMESPACE=1)
         endif()
+        if(GNSSTK_OLDER_THAN_9)
+            target_compile_definitions(run_tests PRIVATE -DGNSSTK_OLDER_THAN_9=1)
+        endif()
     endif()
     if(ENABLE_STRIP)
         set_target_properties(run_tests PROPERTIES LINK_FLAGS "-s")
diff --git a/src/tests/data/gnsstk_static.patch b/src/tests/data/gnsstk_static.patch
deleted file mode 100644
index f660689cd..000000000
--- a/src/tests/data/gnsstk_static.patch
+++ /dev/null
@@ -1,39 +0,0 @@
-SPDX-License-Identifier: GPL-3.0-or-later
-SPDX-FileCopyrightText: 2022 Carles Fernandez-Prades <carles.fernandez@cttc.es>
---- CMakeLists.txt  2022-07-02 20:14:59.000000000 +0200
-+++ CMakeLists.txt  2022-07-02 20:16:55.000000000 +0200
-@@ -6,7 +6,7 @@
- #           Is dependend on by $GNSSTK/build.sh
- #============================================================
-
--cmake_minimum_required( VERSION 2.8.5 )
-+cmake_minimum_required( VERSION 2.8.12 )
-
- project( GNSSTK )
- set( GNSSTK_VERSION_MAJOR "12" )
-@@ -77,6 +77,16 @@
-
-
- include( BuildSetup.cmake )
-+set(STADYN "STATIC")
-+if(POLICY CMP0063)
-+    cmake_policy(SET CMP0063 NEW)
-+    set(CMAKE_CXX_VISIBILITY_PRESET hidden)
-+    set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
-+else()
-+    if((CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "GNU") AND NOT WIN32)
-+        add_definitions(-fvisibility=hidden)
-+    endif()
-+endif()
-
- #============================================================
- # Core Library Target Files
-@@ -161,7 +171,7 @@
- add_library( gnsstk ${STADYN} ${GNSSTK_SRC_FILES} ${GNSSTK_INC_FILES} )
-
- # GNSSTk library install target
--install( TARGETS gnsstk DESTINATION "${CMAKE_INSTALL_LIBDIR}" EXPORT "${EXPORT_TARGETS_FILENAME}" )
-+install( TARGETS gnsstk DESTINATION lib EXPORT "${EXPORT_TARGETS_FILENAME}" )
-
- # GNSSTk header file install target (whether it is version dependent changes based on user flag)
- install( FILES ${GNSSTK_INC_FILES} DESTINATION ${CMAKE_INSTALL_INCLUDEDIR} )
diff --git a/src/tests/data/gnsstk_static13.patch b/src/tests/data/gnsstk_static13.patch
new file mode 100644
index 000000000..daf236cf7
--- /dev/null
+++ b/src/tests/data/gnsstk_static13.patch
@@ -0,0 +1,36 @@
+--- CMakeLists_old.txt	2022-07-10 09:58:33.000000000 +0200
++++ CMakeLists.txt	2022-07-10 10:02:36.000000000 +0200
+@@ -6,7 +6,7 @@
+ #           Is dependend on by $GNSSTK/build.sh
+ #============================================================
+ 
+-cmake_minimum_required( VERSION 2.8.5 )
++cmake_minimum_required( VERSION 2.8.12 )
+ 
+ project( GNSSTK )
+ set( GNSSTK_VERSION_MAJOR "13" )
+@@ -21,6 +21,15 @@
+ 
+ # This sets up variables contining GNU standard installation locations.
+ include( GNUInstallDirs )
++if(POLICY CMP0063)
++    cmake_policy(SET CMP0063 NEW)
++    set(CMAKE_CXX_VISIBILITY_PRESET hidden)
++    set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
++else()
++    if((CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "GNU") AND NOT WIN32)
++        add_definitions(-fvisibility=hidden)
++    endif()
++endif()
+ 
+ # Set a filename for collecting exported targets.
+ set( EXPORT_TARGETS_FILENAME "GNSSTKTargets" )
+@@ -177,7 +186,7 @@
+ elseif( WIN32 )
+   add_library( gnsstk ${GNSSTK_SRC_FILES} ${GNSSTK_INC_FILES} )
+ else()
+-  add_library( gnsstk SHARED ${GNSSTK_SRC_FILES} ${GNSSTK_INC_FILES} )
++  add_library( gnsstk STATIC ${GNSSTK_SRC_FILES} ${GNSSTK_INC_FILES} )
+ endif()
+ 
+ # always generate the header because it's an include file whose
diff --git a/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test.cc b/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test.cc
index 704005402..43388e8b2 100644
--- a/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test.cc
+++ b/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test.cc
@@ -66,6 +66,7 @@
 #include <unistd.h>
 #include <utility>
 #if GNSSTK_USES_GPSTK_NAMESPACE
+#include <gpstk/GPSWeekSecond.hpp>
 #include <gpstk/Rinex3ObsBase.hpp>
 #include <gpstk/Rinex3ObsData.hpp>
 #include <gpstk/Rinex3ObsHeader.hpp>
@@ -73,6 +74,7 @@
 #include <gpstk/RinexUtilities.hpp>
 namespace gnsstk = gpstk;
 #else
+#include <gnsstk/GPSWeekSecond.hpp>
 #include <gnsstk/Rinex3ObsBase.hpp>
 #include <gnsstk/Rinex3ObsData.hpp>
 #include <gnsstk/Rinex3ObsHeader.hpp>
@@ -1612,8 +1614,12 @@ bool HybridObservablesTest::ReadRinexObs(std::vector<arma::mat>* obs_vec, Gnss_S
                                 }
 
                             gnsstk::CommonTime time = r_ref_data.time;
+#if GNSSTK_OLDER_THAN_9
                             double sow(static_cast<gnsstk::GPSWeekSecond>(time).sow);
-
+#else
+                            gnsstk::GPSWeekSecond gws(time);
+                            double sow(gws.getSOW());
+#endif
                             auto pointer = r_ref_data.obs.find(prn);
                             if (pointer == r_ref_data.obs.end())
                                 {
diff --git a/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test_fpga.cc b/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test_fpga.cc
index 74e397d2e..b34f52d86 100644
--- a/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test_fpga.cc
+++ b/src/tests/unit-tests/signal-processing-blocks/observables/hybrid_observables_test_fpga.cc
@@ -67,6 +67,7 @@
 #include <utility>
 
 #if GNSSTK_USES_GPSTK_NAMESPACE
+#include <gpstk/GPSWeekSecond.hpp>
 #include <gpstk/Rinex3ObsBase.hpp>
 #include <gpstk/Rinex3ObsData.hpp>
 #include <gpstk/Rinex3ObsHeader.hpp>
@@ -74,6 +75,7 @@
 #include <gpstk/RinexUtilities.hpp>
 namespace gnsstk = gpstk;
 #else
+#include <gnsstk/GPSWeekSecond.hpp>
 #include <gnsstk/Rinex3ObsBase.hpp>
 #include <gnsstk/Rinex3ObsData.hpp>
 #include <gnsstk/Rinex3ObsHeader.hpp>
@@ -1705,7 +1707,12 @@ bool HybridObservablesTestFpga::ReadRinexObs(std::vector<arma::mat>* obs_vec, Gn
                                 }
 
                             gnsstk::CommonTime time = r_ref_data.time;
+#if GNSSTK_OLDER_THAN_9
                             double sow(static_cast<gnsstk::GPSWeekSecond>(time).sow);
+#else
+                            gnsstk::GPSWeekSecond gws(time);
+                            double sow(gws.getSOW());
+#endif
 
                             auto pointer = r_ref_data.obs.find(prn);
                             if (pointer == r_ref_data.obs.end())
diff --git a/src/utils/rinex-tools/CMakeLists.txt b/src/utils/rinex-tools/CMakeLists.txt
index c2967f231..8eca04cc0 100644
--- a/src/utils/rinex-tools/CMakeLists.txt
+++ b/src/utils/rinex-tools/CMakeLists.txt
@@ -7,7 +7,7 @@
 
 if("${ARMADILLO_VERSION_STRING}" VERSION_GREATER "9.800" OR (NOT ARMADILLO_FOUND) OR ENABLE_OWN_ARMADILLO)  # requires back(), introduced in Armadillo 9.800
     message(STATUS "The obsdiff utility tool will be built when doing '${CMAKE_MAKE_PROGRAM_PRETTY_NAME}'")
-    if(NOT GNSSTK_FOUND)
+    if(NOT GNSSTK_FOUND AND NOT ENABLE_OWN_GNSSTK)
         find_package(GNSSTK)
     endif()
     if(NOT GNSSTK_FOUND OR ENABLE_OWN_GNSSTK)
@@ -67,8 +67,8 @@ if("${ARMADILLO_VERSION_STRING}" VERSION_GREATER "9.800" OR (NOT ARMADILLO_FOUND
     if(GNSSTK_OLDER_THAN_8)
         target_compile_definitions(obsdiff PRIVATE -DOLD_GPSTK=1)
     endif()
-    if(GNSSTK_OLDER_THAN_9)
-        target_compile_definitions(obsdiff PRIVATE -DGNSSTK_OLDER_THAN_9=1)
+    if(GNSSTK_OLDER_THAN_13)
+        target_compile_definitions(obsdiff PRIVATE -DGNSSTK_OLDER_THAN_13=1)
     endif()
     if(NOT TARGET Gnsstk::gnsstk)
         if(GNSSTK_USES_GPSTK_NAMESPACE)
diff --git a/src/utils/rinex-tools/obsdiff.cc b/src/utils/rinex-tools/obsdiff.cc
index f24a6c4cf..60c74fe9f 100644
--- a/src/utils/rinex-tools/obsdiff.cc
+++ b/src/utils/rinex-tools/obsdiff.cc
@@ -36,6 +36,7 @@
 #include <gpstk/GGTropModel.hpp>
 #include <gpstk/GNSSconstants.hpp>
 #include <gpstk/GPSEphemerisStore.hpp>
+#include <gpstk/GPSWeekSecond.hpp>
 #include <gpstk/PRSolution.hpp>
 #include <gpstk/Rinex3NavData.hpp>
 #include <gpstk/Rinex3NavHeader.hpp>
@@ -54,12 +55,6 @@ namespace gnsstk = gpstk;
 #include <gnsstk/Rinex3ObsHeader.hpp>
 #include <gnsstk/Rinex3ObsStream.hpp>
 
-// Classes for handling satellite navigation parameters RINEX
-// files (ephemerides)
-#include <gnsstk/Rinex3NavData.hpp>
-#include <gnsstk/Rinex3NavHeader.hpp>
-#include <gnsstk/Rinex3NavStream.hpp>
-
 // Classes for handling RINEX files with meteorological parameters
 #include <gnsstk/RinexMetBase.hpp>
 #include <gnsstk/RinexMetData.hpp>
@@ -68,15 +63,20 @@ namespace gnsstk = gpstk;
 
 // Class for handling tropospheric model
 #include <gnsstk/GGTropModel.hpp>
-
-// Class for storing >broadcast-type> ephemerides
-#include <gnsstk/GPSEphemerisStore.hpp>
-
-// Class for handling RAIM
+#include <gnsstk/GNSSconstants.hpp>
 #include <gnsstk/PRSolution.hpp>
 
-// Class defining GPS system constants
-#include <gnsstk/GNSSconstants.hpp>
+// Class for storing <broadcast-type> ephemeris
+#include <gnsstk/GPSWeekSecond.hpp>
+#if GNSSTK_OLDER_THAN_13
+#include <gnsstk/GPSEphemerisStore.hpp>
+#include <gnsstk/Rinex3NavData.hpp>
+#include <gnsstk/Rinex3NavHeader.hpp>
+#include <gnsstk/Rinex3NavStream.hpp>
+#else
+#include <gnsstk/MultiFormatNavDataFactory.hpp>
+#include <gnsstk/NavLibrary.hpp>
+#endif
 #endif
 
 #if GFLAGS_OLD_NAMESPACE
@@ -161,7 +161,13 @@ std::map<int, arma::mat> ReadRinexObs(const std::string& rinex_file, char system
                         {
                             prn.id = prn_it;
                             gnsstk::CommonTime time = r_base_data.time;
+
+#if GNSSTK_OLDER_THAN_9
                             double sow(static_cast<gnsstk::GPSWeekSecond>(time).sow);
+#else
+                            gnsstk::GPSWeekSecond gws(time);
+                            double sow(gws.getSOW());
+#endif
 
                             auto pointer = r_base_data.obs.find(prn);
 
@@ -1153,8 +1159,17 @@ double compute_rx_clock_error(const std::string& rinex_nav_filename, const std::
             std::cout << "Warning: RINEX Nav file " << rinex_nav_filename << " does not exist, receiver's clock error could not be computed!\n";
             return 0.0;
         }
-    // Declaration of objects for storing ephemerides and handling RAIM
+        // Declaration of objects for storing ephemerides and handling RAIM
+#if GNSSTK_OLDER_THAN_13
     gnsstk::GPSEphemerisStore bcestore;
+#else
+    gnsstk::NavLibrary navLib;
+    // Construct a NavDataFactory object
+    gnsstk::NavDataFactoryPtr ndfp(
+        std::make_shared<gnsstk::MultiFormatNavDataFactory>());
+    // Add the NavDataFactory to the NavLibrary
+    navLib.addFactory(ndfp);
+#endif
     gnsstk::PRSolution raimSolver;
 
     // Object for void-type tropospheric model (in case no meteorological
@@ -1172,22 +1187,26 @@ double compute_rx_clock_error(const std::string& rinex_nav_filename, const std::
     double rx_clock_error_s = 0.0;
     try
         {
+#if GNSSTK_OLDER_THAN_13
             // Read nav file and store unique list of ephemerides
             gnsstk::Rinex3NavStream rnffs(rinex_nav_filename.c_str());  // Open ephemerides data file
             gnsstk::Rinex3NavData rne;
             gnsstk::Rinex3NavHeader hdr;
-
             // Let's read the header (may be skipped)
             rnffs >> hdr;
-
-            // Storing the ephemeris in "bcstore"
             while (rnffs >> rne)
                 {
                     bcestore.addEphemeris(rne);
                 }
-
             // Setting the criteria for looking up ephemeris
             bcestore.SearchNear();
+#else
+            if (!ndfp->addDataSource(rinex_nav_filename))
+                {
+                    std::cerr << "Unable to load " << rinex_nav_filename << '\n';
+                    return 0.0;
+                }
+#endif
 
             // Open and read the observation file one epoch at a time.
             // For each epoch, compute and print a position solution
@@ -1280,8 +1299,13 @@ double compute_rx_clock_error(const std::string& rinex_nav_filename, const std::
                                     iret = raimSolver.RAIMCompute(rod.time, prnVec, Syss, rangeVec, invMC,
                                         &bcestore, tropModelPtr);
 #else
+#if GNSSTK_OLDER_THAN_13
                                     iret = raimSolver.RAIMCompute(rod.time, prnVec, rangeVec, invMC,
                                         &bcestore, tropModelPtr);
+#else
+                                    iret = raimSolver.RAIMCompute(rod.time, prnVec, rangeVec, invMC,
+                                        navLib, tropModelPtr);
+#endif
 #endif
                                     switch (iret)
                                         {
diff --git a/src/utils/rinex2assist/CMakeLists.txt b/src/utils/rinex2assist/CMakeLists.txt
index 4b8c61b63..1f83c829d 100644
--- a/src/utils/rinex2assist/CMakeLists.txt
+++ b/src/utils/rinex2assist/CMakeLists.txt
@@ -4,7 +4,7 @@
 # SPDX-FileCopyrightText: 2010-2020 C. Fernandez-Prades cfernandez(at)cttc.es
 # SPDX-License-Identifier: BSD-3-Clause
 
-if(NOT GNSSTK_FOUND)
+if(NOT GNSSTK_FOUND AND NOT ENABLE_OWN_GNSSTK)
     find_package(GNSSTK)
 endif()
 
@@ -98,10 +98,8 @@ if(Boost_FOUND)
                 ${GNSSTK_INCLUDE_DIR}
         )
     endif()
-    if(GNSSTK_VERSION)
-        if(GNSSTK_VERSION VERSION_LESS "9.0.0")
-            target_compile_definitions(rinex2assist PRIVATE -DGNSSTK_OLDER_THAN_9=1)
-        endif()
+    if(GNSSTK_OLDER_THAN_9)
+        target_compile_definitions(rinex2assist PRIVATE -DGNSSTK_OLDER_THAN_9=1)
     endif()
 
     if(NOT UNCOMPRESS_EXECUTABLE-NOTFOUND)