diff --git a/test/meson.build b/test/meson.build
index 300e977..ae1b8e6 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -27,6 +27,7 @@
 tests = [
   'utest.cpp',
   'utest-led-json.cpp',
+  'utest-group-priority.cpp',
 ]
 if get_option('persistent-led-asserted').allowed()
   test_sources += [
diff --git a/test/utest-group-priority.cpp b/test/utest-group-priority.cpp
new file mode 100644
index 0000000..43fa289
--- /dev/null
+++ b/test/utest-group-priority.cpp
@@ -0,0 +1,379 @@
+#include "ledlayout.hpp"
+#include "manager.hpp"
+
+#include <sdbusplus/bus.hpp>
+#include <xyz/openbmc_project/Led/Physical/server.hpp>
+
+#include <set>
+
+#include <gtest/gtest.h>
+
+using namespace phosphor::led;
+class LedTest : public ::testing::Test
+{
+  public:
+    sdbusplus::bus_t bus;
+    LedTest() : bus(sdbusplus::bus::new_default())
+    {
+        // Nothing here
+    }
+    ~LedTest()
+    {
+        // Leaving up to auto cleanup.
+    }
+};
+
+static void assertMap(std::map<LedName, Layout::LedAction> map,
+                      std::map<LedName, Layout::Action> expect)
+{
+    EXPECT_EQ(map.size(), expect.size());
+    for (auto& [key, expect_value] : expect)
+    {
+        ASSERT_TRUE(map.contains(key));
+        EXPECT_EQ(expect_value, map[key].action);
+    }
+}
+
+static const phosphor::led::GroupMap groups1 = {
+    {"/xyz/openbmc_project/ledmanager/groups/groupA",
+     {0,
+      {
+          {"led1", Layout::Action::On, 0, 0, std::nullopt},
+          {"led2", Layout::Action::On, 0, 0, std::nullopt},
+      }}},
+    {"/xyz/openbmc_project/ledmanager/groups/groupB",
+     {0,
+      {
+          {"led3", Layout::Action::On, 0, 0, std::nullopt},
+          {"led4", Layout::Action::On, 0, 0, std::nullopt},
+      }}},
+};
+
+/** @brief Assert one group*/
+TEST_F(LedTest, assertOneGroup)
+{
+    Manager manager(bus, groups1);
+
+    std::set<const Layout::GroupLayout*> assertedGroups;
+
+    Layout::GroupLayout mygroup =
+        groups1.at("/xyz/openbmc_project/ledmanager/groups/groupA");
+
+    assertedGroups.insert(&mygroup);
+
+    std::map<LedName, Layout::LedAction> map =
+        manager.getNewMap(assertedGroups);
+
+    assertMap(map, {
+                       {"led1", Layout::Action::On},
+                       {"led2", Layout::Action::On},
+                   });
+}
+
+static const phosphor::led::GroupMap groups2 = {
+    {"/xyz/openbmc_project/ledmanager/groups/groupA",
+     {0,
+      {
+          {"led1", Layout::Action::On, 0, 0, std::nullopt},
+          {"led2", Layout::Action::On, 0, 0, std::nullopt},
+      }}},
+    {"/xyz/openbmc_project/ledmanager/groups/groupB",
+     {2,
+      {
+          {"led2", Layout::Action::Off, 0, 0, std::nullopt},
+          {"led3", Layout::Action::On, 0, 0, std::nullopt},
+      }}},
+    {"/xyz/openbmc_project/ledmanager/groups/groupC",
+     {1,
+      {
+          {"led3", Layout::Action::Blink, 0, 0, std::nullopt},
+          {"led4", Layout::Action::Blink, 0, 0, std::nullopt},
+      }}},
+};
+
+/** @brief Assert multiple groups which overwrite each other*/
+TEST_F(LedTest, assertMultipleGroups)
+{
+    Manager manager(bus, groups2);
+
+    std::set<const Layout::GroupLayout*> assertedGroups;
+
+    Layout::GroupLayout groupA =
+        groups2.at("/xyz/openbmc_project/ledmanager/groups/groupA");
+    Layout::GroupLayout groupB =
+        groups2.at("/xyz/openbmc_project/ledmanager/groups/groupB");
+    Layout::GroupLayout groupC =
+        groups2.at("/xyz/openbmc_project/ledmanager/groups/groupC");
+
+    assertedGroups.insert(&groupA);
+    assertedGroups.insert(&groupB);
+    assertedGroups.insert(&groupC);
+
+    std::map<LedName, Layout::LedAction> map =
+        manager.getNewMap(assertedGroups);
+
+    assertMap(map, {
+                       {"led1", Layout::Action::On},
+                       {"led2", Layout::Action::Off},
+                       {"led3", Layout::Action::On},
+                       {"led4", Layout::Action::Blink},
+                   });
+}
+
+TEST_F(LedTest, test_OCP_Panel_Indicator_6_1_System_Power_Status)
+{
+    const int dutyon = 50; // Spec says 50% duty cycle
+    const int period = 1;  // Spec says 1Hz
+
+    // Example from OCP Panel Indicator Specification rev 1.0, Section 6.1
+    // "System Power Control / Status"
+    // The group priorities here are chosen arbitrarily, assuming that locating
+    // the hw has highest priority
+    const std::string groupOffServiceAction =
+        "/xyz/openbmc_project/ledmanager/groups/SysOffServiceAction";
+    const std::string groupSysOnOk =
+        "/xyz/openbmc_project/ledmanager/groups/SysOnOK";
+    const std::string groupSysOffFault =
+        "/xyz/openbmc_project/ledmanager/groups/SysOffFault";
+    const std::string groupSysOnLocate =
+        "/xyz/openbmc_project/ledmanager/groups/SysOnLocate";
+    const std::string groupSysOffLocate =
+        "/xyz/openbmc_project/ledmanager/groups/SysOffLocate";
+    const std::string groupSysOnFault =
+        "/xyz/openbmc_project/ledmanager/groups/SysOnFault";
+
+    const std::string pwr = "pwr";
+    const std::string fault = "fault";
+
+    static const phosphor::led::GroupMap groups_ocp_6_1_power_control = {
+        {groupOffServiceAction,
+         {2,
+          {
+              {pwr, Layout::Action::Off, 0, 0, std::nullopt},
+              {fault, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+        {groupSysOnOk,
+         {3,
+          {
+              {pwr, Layout::Action::On, 0, 0, std::nullopt},
+              {fault, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+        {groupSysOffFault,
+         {38,
+          {
+              {pwr, Layout::Action::Off, 0, 0, std::nullopt},
+              {fault, Layout::Action::On, 0, 0, std::nullopt},
+          }}},
+        {groupSysOnLocate,
+         {99,
+          {
+              {pwr, Layout::Action::On, 0, 0, std::nullopt},
+              {fault, Layout::Action::Blink, dutyon, period, std::nullopt},
+          }}},
+        {groupSysOffLocate,
+         {98,
+          {
+              {pwr, Layout::Action::Off, 0, 0, std::nullopt},
+              {fault, Layout::Action::Blink, dutyon, period, std::nullopt},
+          }}},
+        {groupSysOnFault,
+         {39,
+          {
+              {pwr, Layout::Action::On, 0, 0, std::nullopt},
+              {fault, Layout::Action::On, 0, 0, std::nullopt},
+          }}},
+    };
+
+    const phosphor::led::GroupMap* groups = &groups_ocp_6_1_power_control;
+
+    Manager manager(bus, *groups);
+
+    std::set<const Layout::GroupLayout*> assertedGroups;
+
+    // Off Service Action
+    assertedGroups.insert(&groups->at(groupOffServiceAction));
+
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {pwr, Layout::Action::Off},
+                  {fault, Layout::Action::Off},
+              });
+
+    // On Ok
+    assertedGroups.insert(&groups->at(groupSysOnOk));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {pwr, Layout::Action::On},
+                  {fault, Layout::Action::Off},
+              });
+
+    // Off Fault
+    assertedGroups.insert(&groups->at(groupSysOffFault));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {pwr, Layout::Action::Off},
+                  {fault, Layout::Action::On},
+              });
+
+    // Off Fault
+    assertedGroups.insert(&groups->at(groupSysOffFault));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {pwr, Layout::Action::Off},
+                  {fault, Layout::Action::On},
+              });
+
+    // On Fault
+    assertedGroups.insert(&groups->at(groupSysOnFault));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {pwr, Layout::Action::On},
+                  {fault, Layout::Action::On},
+              });
+
+    // Off Locate
+    assertedGroups.insert(&groups->at(groupSysOffLocate));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {pwr, Layout::Action::Off},
+                  {fault, Layout::Action::Blink},
+              });
+
+    // On Locate
+    assertedGroups.insert(&groups->at(groupSysOnLocate));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {pwr, Layout::Action::On},
+                  {fault, Layout::Action::Blink},
+              });
+}
+
+TEST_F(LedTest, test_OCP_Panel_Indicator_6_5_BBU_status)
+{
+    // Example from OCP Panel Indicator Specification rev 1.0, Section 6.5
+    // "BBU Status"
+    // The group priorities here are chosen arbitrarily, assuming that locating
+    // the hw has highest priority
+    const std::string gBBUSleep =
+        "/xyz/openbmc_project/ledmanager/groups/BBUSleep";
+    const std::string gBBUOn = "/xyz/openbmc_project/ledmanager/groups/BBUOn";
+    const std::string gBBUFault =
+        "/xyz/openbmc_project/ledmanager/groups/BBUFault";
+    const std::string gBBUUnderVolt =
+        "/xyz/openbmc_project/ledmanager/groups/BBUUnderVolt";
+    const std::string gBBUEOL = "/xyz/openbmc_project/ledmanager/groups/BBUEOL";
+    const std::string gBBUOffLocate =
+        "/xyz/openbmc_project/ledmanager/groups/BBUOffLocate";
+    const std::string gBBUOnLocate =
+        "/xyz/openbmc_project/ledmanager/groups/BBUOnLocate";
+
+    const std::string bbu_ok = "bbu_ok";
+    const std::string bbu_fault = "bbu_fault";
+    const std::string bbu_lowv = "bbu_lowv";
+    const std::string bbu_eol = "bbu_eol";
+
+    static const phosphor::led::GroupMap groups_ocp_6_5_bbu_status = {
+        {gBBUSleep,
+         {9,
+          {
+              {bbu_ok, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_fault, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_lowv, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_eol, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+        {gBBUOn,
+         {10,
+          {
+              {bbu_ok, Layout::Action::On, 0, 0, std::nullopt},
+              {bbu_fault, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_lowv, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_eol, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+        {gBBUFault,
+         {38,
+          {
+              {bbu_ok, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_fault, Layout::Action::On, 0, 0, std::nullopt},
+              {bbu_lowv, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_eol, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+        {gBBUUnderVolt,
+         {39,
+          {
+              {bbu_ok, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_fault, Layout::Action::On, 0, 0, std::nullopt},
+              {bbu_lowv, Layout::Action::On, 0, 0, std::nullopt},
+              {bbu_eol, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+        {gBBUEOL,
+         {40,
+          {
+              {bbu_ok, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_fault, Layout::Action::On, 0, 0, std::nullopt},
+              {bbu_lowv, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_eol, Layout::Action::On, 0, 0, std::nullopt},
+          }}},
+        {gBBUOffLocate,
+         {98,
+          {
+              {bbu_ok, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_fault, Layout::Action::Blink, 0, 0, std::nullopt},
+              {bbu_lowv, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_eol, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+        {gBBUOnLocate,
+         {99,
+          {
+              {bbu_ok, Layout::Action::On, 0, 0, std::nullopt},
+              {bbu_fault, Layout::Action::Blink, 0, 0, std::nullopt},
+              {bbu_lowv, Layout::Action::Off, 0, 0, std::nullopt},
+              {bbu_eol, Layout::Action::Off, 0, 0, std::nullopt},
+          }}},
+    };
+
+    const phosphor::led::GroupMap* groups = &groups_ocp_6_5_bbu_status;
+
+    Manager manager(bus, *groups);
+
+    std::set<const Layout::GroupLayout*> assertedGroups;
+
+    // Sleep
+    assertedGroups.insert(&groups->at(gBBUSleep));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {bbu_ok, Layout::Action::Off},
+                  {bbu_fault, Layout::Action::Off},
+                  {bbu_lowv, Layout::Action::Off},
+                  {bbu_eol, Layout::Action::Off},
+              });
+
+    // Fault
+    assertedGroups.insert(&groups->at(gBBUFault));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {bbu_ok, Layout::Action::Off},
+                  {bbu_fault, Layout::Action::On},
+                  {bbu_lowv, Layout::Action::Off},
+                  {bbu_eol, Layout::Action::Off},
+              });
+
+    // EOL
+    assertedGroups.insert(&groups->at(gBBUEOL));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {bbu_ok, Layout::Action::Off},
+                  {bbu_fault, Layout::Action::On},
+                  {bbu_lowv, Layout::Action::Off},
+                  {bbu_eol, Layout::Action::On},
+              });
+
+    // On + Locate
+    assertedGroups.insert(&groups->at(gBBUOnLocate));
+    assertMap(manager.getNewMap(assertedGroups),
+              {
+                  {bbu_ok, Layout::Action::On},
+                  {bbu_fault, Layout::Action::Blink},
+                  {bbu_lowv, Layout::Action::Off},
+                  {bbu_eol, Layout::Action::Off},
+              });
+}