diff --git a/src/lighthouse.c b/src/lighthouse.c
index 96b42b333..dd1183558 100644
--- a/src/lighthouse.c
+++ b/src/lighthouse.c
@@ -73,13 +73,11 @@ int lighthouse_range(const building * b, const faction * f)
             region *r = b->region;
             int c = 0;
             int cap = buildingcapacity(b);
-            unit *u;
+            unit *u, *uown = building_owner(b);
 
             for (u = r->units; u; u = u->next) {
-                if (u->building == b || u == building_owner(b)) {
-                    if (u->building == b) {
-                        c += u->number;
-                    }
+                if (u->building == b || u == uown) {
+                    c += u->number;
                     if (c > cap) {
                         break;
                     }
diff --git a/src/reports.c b/src/reports.c
index dc0edf1b3..5a7f29a10 100644
--- a/src/reports.c
+++ b/src/reports.c
@@ -1170,11 +1170,9 @@ static void add_seen_nb(faction *f, region *r, seen_mode mode) {
 
 /** mark all regions seen by the lighthouse.
  */
-static void prepare_lighthouse(building * b, report_context *ctx)
+static void prepare_lighthouse(faction *f, region *r, int range)
 {
-    faction *f = ctx->f;
-    int range = lighthouse_range(b, f);
-    quicklist *ql, *rlist = get_regions_distance(b->region, range);
+    quicklist *ql, *rlist = get_regions_distance(r, range);
     int qi;
 
     for (ql = rlist, qi = 0; ql; ql_advance(&ql, &qi, 1)) {
@@ -1316,7 +1314,6 @@ static void cb_add_seen(region *r, unit *u, void *cbdata) {
 void prepare_report(report_context *ctx, faction *f)
 {
     region *r;
-    building *b;
     static int config;
     static bool rule_region_owners;
     const struct building_type *bt_lighthouse = bt_find("lighthouse");
@@ -1334,34 +1331,36 @@ void prepare_report(report_context *ctx, faction *f)
     ctx->last = lastregion(f);
 
     for (r = ctx->first; r!=ctx->last; r = r->next) {
+        int range = 0;
         unit *u;
+        if (fval(r, RF_LIGHTHOUSE) && bt_lighthouse) {
+            if (rule_region_owners && f == region_get_owner(r)) {
+                /* region owners get the report from lighthouses */
+                building *b;
 
-        if (fval(r, RF_LIGHTHOUSE)) {
-            /* region owners get the report from lighthouses */
-            if (rule_region_owners && bt_lighthouse) {
-                for (b = rbuildings(r); b; b = b->next) {
-                    if (b && b->type == bt_lighthouse) {
-                        u = building_owner(b);
-                        if (u && u->faction==f) {
-                            prepare_lighthouse(b, ctx);
-                            add_seen_nb(f, r, seen_unit);
-                        }
+                for (b = r->buildings; b; b = b->next) {
+                    if (b->type == bt_lighthouse) {
+                        int br = lighthouse_range(b, NULL);
+                        if (br > range) range = br;
                     }
                 }
             }
-
         }
         for (u = r->units; u; u = u->next) {
-            if (u->faction==f) {
+            if (u->faction == f) {
                 add_seen_nb(f, r, seen_unit);
-                if (fval(r, RF_LIGHTHOUSE)) {
+                if (fval(r, RF_LIGHTHOUSE) && bt_lighthouse) {
                     if (u->building && u->building->type == bt_lighthouse && inside_building(u)) {
-                        /* we are in a lighthouse. add the regions we can see from here! */
-                        prepare_lighthouse(u->building, ctx);
+                        int br = lighthouse_range(u->building, f);
+                        if (br > range) range = br;
                     }
                 }
             }
         }
+        if (range > 0) {
+            /* we are in at least one lighthouse. add the regions we can see from here! */
+            prepare_lighthouse(f, r, range);
+        }
 
         if (fval(r, RF_TRAVELUNIT) && r->seen.mode<seen_travel) {
             travelthru_map(r, cb_add_seen, f);
diff --git a/src/reports.test.c b/src/reports.test.c
index d9b427ff2..bc89bb4b4 100644
--- a/src/reports.test.c
+++ b/src/reports.test.c
@@ -7,6 +7,7 @@
 #include "travelthru.h"
 #include "keyword.h"
 
+#include <kernel/config.h>
 #include <kernel/building.h>
 #include <kernel/faction.h>
 #include <kernel/item.h>
@@ -344,6 +345,43 @@ static void test_prepare_lighthouse(CuTest *tc) {
     test_cleanup();
 }
 
+static void test_prepare_lighthouse_owners(CuTest *tc) {
+    report_context ctx;
+    faction *f;
+    region *r1, *r2, *r3;
+    unit *u;
+    building *b;
+    building_type *btype;
+    const struct terrain_type *t_ocean, *t_plain;
+
+    test_setup();
+    config_set("rules.region_owner_pay_building", "lighthouse");
+    config_set("rules.region_owners", "1");
+    t_ocean = test_create_terrain("ocean", SEA_REGION);
+    t_plain = test_create_terrain("plain", LAND_REGION);
+    f = test_create_faction(0);
+    r1 = test_create_region(0, 0, t_plain);
+    r2 = test_create_region(1, 0, t_ocean);
+    r3 = test_create_region(2, 0, t_ocean);
+    btype = test_create_buildingtype("lighthouse");
+    b = test_create_building(r1, btype);
+    b->flags |= BLD_MAINTAINED;
+    b->size = 10;
+    update_lighthouse(b);
+    u = test_create_unit(f, r1);
+    u = test_create_unit(test_create_faction(0), r1);
+    u->building = b;
+    set_level(u, SK_PERCEPTION, 3);
+    region_set_owner(b->region, f, 0);
+    prepare_report(&ctx, f);
+    CuAssertPtrEquals(tc, r1, ctx.first);
+    CuAssertPtrEquals(tc, NULL, ctx.last);
+    CuAssertIntEquals(tc, seen_unit, r1->seen.mode);
+    CuAssertIntEquals(tc, seen_lighthouse, r2->seen.mode);
+    CuAssertIntEquals(tc, seen_neighbour, r3->seen.mode);
+    test_cleanup();
+}
+
 static void test_prepare_report(CuTest *tc) {
     report_context ctx;
     faction *f;
@@ -432,6 +470,7 @@ CuSuite *get_reports_suite(void)
     SUITE_ADD_TEST(suite, test_seen_neighbours);
     SUITE_ADD_TEST(suite, test_seen_travelthru);
     SUITE_ADD_TEST(suite, test_prepare_lighthouse);
+    SUITE_ADD_TEST(suite, test_prepare_lighthouse_owners);
     SUITE_ADD_TEST(suite, test_prepare_lighthouse_capacity);
     SUITE_ADD_TEST(suite, test_prepare_travelthru);
     SUITE_ADD_TEST(suite, test_reorder_units);