diff --git a/src/industry_cmd.cpp b/src/industry_cmd.cpp
index e3f7d197b2..56dfcbc430 100644
--- a/src/industry_cmd.cpp
+++ b/src/industry_cmd.cpp
@@ -483,8 +483,8 @@ static void GetTileDesc_Industry(TileIndex tile, TileDesc *td)
 		td->str = STR_LAI_TOWN_INDUSTRY_DESCRIPTION_UNDER_CONSTRUCTION;
 	}
 
-	if (is->grf_prop.grffile != nullptr) {
-		td->grf = GetGRFConfig(is->grf_prop.grffile->grfid)->GetName();
+	if (is->grf_prop.HasGrfFile()) {
+		td->grf = GetGRFConfig(is->grf_prop.grfid)->GetName();
 	}
 }
 
@@ -1826,7 +1826,7 @@ static void DoCreateNewIndustry(Industry *i, TileIndex tile, IndustryType type,
 		uint16_t res = GetIndustryCallback(CBID_INDUSTRY_PROD_CHANGE_BUILD, 0, Random(), i, type, INVALID_TILE);
 		if (res != CALLBACK_FAILED) {
 			if (res < PRODLEVEL_MINIMUM || res > PRODLEVEL_MAXIMUM) {
-				ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_PROD_CHANGE_BUILD, res);
+				ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_PROD_CHANGE_BUILD, res);
 			} else {
 				i->prod_level = res;
 				i->RecomputeProductionMultipliers();
@@ -1851,7 +1851,7 @@ static void DoCreateNewIndustry(Industry *i, TileIndex tile, IndustryType type,
 	if (HasBit(indspec->callback_mask, CBM_IND_DECIDE_COLOUR)) {
 		uint16_t res = GetIndustryCallback(CBID_INDUSTRY_DECIDE_COLOUR, 0, 0, i, type, INVALID_TILE);
 		if (res != CALLBACK_FAILED) {
-			if (GB(res, 4, 11) != 0) ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_DECIDE_COLOUR, res);
+			if (GB(res, 4, 11) != 0) ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_DECIDE_COLOUR, res);
 			i->random_colour = static_cast<Colours>(GB(res, 0, 4));
 		}
 	}
@@ -1865,7 +1865,7 @@ static void DoCreateNewIndustry(Industry *i, TileIndex tile, IndustryType type,
 			uint16_t res = GetIndustryCallback(CBID_INDUSTRY_INPUT_CARGO_TYPES, j, 0, i, type, INVALID_TILE);
 			if (res == CALLBACK_FAILED || GB(res, 0, 8) == UINT8_MAX) break;
 			if (indspec->grf_prop.grffile->grf_version >= 8 && res >= 0x100) {
-				ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_INPUT_CARGO_TYPES, res);
+				ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_INPUT_CARGO_TYPES, res);
 				break;
 			}
 			CargoID cargo = GetCargoTranslation(GB(res, 0, 8), indspec->grf_prop.grffile);
@@ -1881,12 +1881,12 @@ static void DoCreateNewIndustry(Industry *i, TileIndex tile, IndustryType type,
 			/* Verify valid cargo */
 			if (std::ranges::find(indspec->accepts_cargo, cargo) == std::end(indspec->accepts_cargo)) {
 				/* Cargo not in spec, error in NewGRF */
-				ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_INPUT_CARGO_TYPES, res);
+				ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_INPUT_CARGO_TYPES, res);
 				break;
 			}
 			if (std::any_of(std::begin(i->accepted), std::begin(i->accepted) + j, [&cargo](const auto &a) { return a.cargo == cargo; })) {
 				/* Duplicate cargo */
-				ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_INPUT_CARGO_TYPES, res);
+				ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_INPUT_CARGO_TYPES, res);
 				break;
 			}
 			Industry::AcceptedCargo &a = i->accepted.emplace_back();
@@ -1903,7 +1903,7 @@ static void DoCreateNewIndustry(Industry *i, TileIndex tile, IndustryType type,
 			uint16_t res = GetIndustryCallback(CBID_INDUSTRY_OUTPUT_CARGO_TYPES, j, 0, i, type, INVALID_TILE);
 			if (res == CALLBACK_FAILED || GB(res, 0, 8) == UINT8_MAX) break;
 			if (indspec->grf_prop.grffile->grf_version >= 8 && res >= 0x100) {
-				ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_OUTPUT_CARGO_TYPES, res);
+				ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_OUTPUT_CARGO_TYPES, res);
 				break;
 			}
 			CargoID cargo = GetCargoTranslation(GB(res, 0, 8), indspec->grf_prop.grffile);
@@ -1917,12 +1917,12 @@ static void DoCreateNewIndustry(Industry *i, TileIndex tile, IndustryType type,
 			/* Verify valid cargo */
 			if (std::ranges::find(indspec->produced_cargo, cargo) == std::end(indspec->produced_cargo)) {
 				/* Cargo not in spec, error in NewGRF */
-				ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_OUTPUT_CARGO_TYPES, res);
+				ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_OUTPUT_CARGO_TYPES, res);
 				break;
 			}
 			if (std::any_of(std::begin(i->produced), std::begin(i->produced) + j, [&cargo](const auto &p) { return p.cargo == cargo; })) {
 				/* Duplicate cargo */
-				ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_OUTPUT_CARGO_TYPES, res);
+				ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_OUTPUT_CARGO_TYPES, res);
 				break;
 			}
 			Industry::ProducedCargo &p = i->produced.emplace_back();
@@ -2812,7 +2812,7 @@ static void ChangeIndustryProduction(Industry *i, bool monthly)
 		if (res != CALLBACK_FAILED) { // failed callback means "do nothing"
 			suppress_message = HasBit(res, 7);
 			/* Get the custom message if any */
-			if (HasBit(res, 8)) str = MapGRFStringID(indspec->grf_prop.grffile->grfid, GB(GetRegister(0x100), 0, 16));
+			if (HasBit(res, 8)) str = MapGRFStringID(indspec->grf_prop.grfid, GB(GetRegister(0x100), 0, 16));
 			res = GB(res, 0, 4);
 			switch (res) {
 				default: NOT_REACHED();
diff --git a/src/industry_gui.cpp b/src/industry_gui.cpp
index ef584464bb..ac984b1a9f 100644
--- a/src/industry_gui.cpp
+++ b/src/industry_gui.cpp
@@ -104,12 +104,12 @@ static void GetCargoSuffix(uint cargo, CargoSuffixType cst, const Industry *ind,
 			if (GB(callback, 0, 8) == 0xFF) return;
 			if (callback < 0x400) {
 				StartTextRefStackUsage(indspec->grf_prop.grffile, 6);
-				suffix.text = GetString(GetGRFStringID(indspec->grf_prop.grffile->grfid, 0xD000 + callback));
+				suffix.text = GetString(GetGRFStringID(indspec->grf_prop.grfid, 0xD000 + callback));
 				StopTextRefStackUsage();
 				suffix.display = CSD_CARGO_AMOUNT_TEXT;
 				return;
 			}
-			ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_CARGO_SUFFIX, callback);
+			ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_CARGO_SUFFIX, callback);
 			return;
 
 		} else { // GRF version 8 or higher.
@@ -120,19 +120,19 @@ static void GetCargoSuffix(uint cargo, CargoSuffixType cst, const Industry *ind,
 			}
 			if (callback < 0x400) {
 				StartTextRefStackUsage(indspec->grf_prop.grffile, 6);
-				suffix.text = GetString(GetGRFStringID(indspec->grf_prop.grffile->grfid, 0xD000 + callback));
+				suffix.text = GetString(GetGRFStringID(indspec->grf_prop.grfid, 0xD000 + callback));
 				StopTextRefStackUsage();
 				suffix.display = CSD_CARGO_AMOUNT_TEXT;
 				return;
 			}
 			if (callback >= 0x800 && callback < 0xC00) {
 				StartTextRefStackUsage(indspec->grf_prop.grffile, 6);
-				suffix.text = GetString(GetGRFStringID(indspec->grf_prop.grffile->grfid, 0xD000 - 0x800 + callback));
+				suffix.text = GetString(GetGRFStringID(indspec->grf_prop.grfid, 0xD000 - 0x800 + callback));
 				StopTextRefStackUsage();
 				suffix.display = CSD_CARGO_TEXT;
 				return;
 			}
-			ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_CARGO_SUFFIX, callback);
+			ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_CARGO_SUFFIX, callback);
 			return;
 		}
 	}
@@ -477,7 +477,7 @@ public:
 					}
 					d = maxdim(d, strdim);
 
-					if (indsp->grf_prop.grffile != nullptr) {
+					if (indsp->grf_prop.HasGrfFile()) {
 						/* Reserve a few extra lines for text from an industry NewGRF. */
 						extra_lines_newgrf = 4;
 					}
@@ -588,9 +588,9 @@ public:
 					uint16_t callback_res = GetIndustryCallback(CBID_INDUSTRY_FUND_MORE_TEXT, 0, 0, nullptr, this->selected_type, INVALID_TILE);
 					if (callback_res != CALLBACK_FAILED && callback_res != 0x400) {
 						if (callback_res > 0x400) {
-							ErrorUnknownCallbackResult(indsp->grf_prop.grffile->grfid, CBID_INDUSTRY_FUND_MORE_TEXT, callback_res);
+							ErrorUnknownCallbackResult(indsp->grf_prop.grfid, CBID_INDUSTRY_FUND_MORE_TEXT, callback_res);
 						} else {
-							StringID str = GetGRFStringID(indsp->grf_prop.grffile->grfid, 0xD000 + callback_res);  // No. here's the new string
+							StringID str = GetGRFStringID(indsp->grf_prop.grfid, 0xD000 + callback_res);  // No. here's the new string
 							if (str != STR_UNDEFINED) {
 								StartTextRefStackUsage(indsp->grf_prop.grffile, 6);
 								DrawStringMultiLine(ir, str, TC_YELLOW);
@@ -981,9 +981,9 @@ public:
 			uint16_t callback_res = GetIndustryCallback(CBID_INDUSTRY_WINDOW_MORE_TEXT, 0, 0, i, i->type, i->location.tile);
 			if (callback_res != CALLBACK_FAILED && callback_res != 0x400) {
 				if (callback_res > 0x400) {
-					ErrorUnknownCallbackResult(ind->grf_prop.grffile->grfid, CBID_INDUSTRY_WINDOW_MORE_TEXT, callback_res);
+					ErrorUnknownCallbackResult(ind->grf_prop.grfid, CBID_INDUSTRY_WINDOW_MORE_TEXT, callback_res);
 				} else {
-					StringID message = GetGRFStringID(ind->grf_prop.grffile->grfid, 0xD000 + callback_res);
+					StringID message = GetGRFStringID(ind->grf_prop.grfid, 0xD000 + callback_res);
 					if (message != STR_NULL && message != STR_UNDEFINED) {
 						ir.top += WidgetDimensions::scaled.vsep_wide;
 
diff --git a/src/newgrf.cpp b/src/newgrf.cpp
index 1978e0ca6a..2a4449fd19 100644
--- a/src/newgrf.cpp
+++ b/src/newgrf.cpp
@@ -632,7 +632,10 @@ static Engine *GetNewEngine(const GRFFile *file, VehicleType type, uint16_t inte
 		EngineID engine = _engine_mngr.GetID(type, internal_id, scope_grfid);
 		if (engine != INVALID_ENGINE) {
 			Engine *e = Engine::Get(engine);
-			if (e->grf_prop.grffile == nullptr) e->grf_prop.grffile = file;
+			if (!e->grf_prop.HasGrfFile()) {
+				e->grf_prop.grfid = file->grfid;
+				e->grf_prop.grffile = file;
+			}
 			return e;
 		}
 	}
@@ -642,7 +645,8 @@ static Engine *GetNewEngine(const GRFFile *file, VehicleType type, uint16_t inte
 	if (engine != INVALID_ENGINE) {
 		Engine *e = Engine::Get(engine);
 
-		if (e->grf_prop.grffile == nullptr) {
+		if (!e->grf_prop.HasGrfFile()) {
+			e->grf_prop.grfid = file->grfid;
 			e->grf_prop.grffile = file;
 			GrfMsg(5, "Replaced engine at index {} for GRFID {:x}, type {}, index {}", e->index, BSWAP32(file->grfid), type, internal_id);
 		}
@@ -667,6 +671,7 @@ static Engine *GetNewEngine(const GRFFile *file, VehicleType type, uint16_t inte
 
 	/* ... it's not, so create a new one based off an existing engine */
 	Engine *e = new Engine(type, internal_id);
+	e->grf_prop.grfid = file->grfid;
 	e->grf_prop.grffile = file;
 
 	/* Reserve the engine slot */
@@ -2463,6 +2468,7 @@ static ChangeInfoResult TownHouseChangeInfo(uint hid, int numinfo, int prop, Byt
 					housespec->enabled = true;
 					housespec->grf_prop.local_id = hid + i;
 					housespec->grf_prop.subst_id = subs_id;
+					housespec->grf_prop.grfid = _cur.grffile->grfid;
 					housespec->grf_prop.grffile = _cur.grffile;
 					/* Set default colours for randomization, used if not overridden. */
 					housespec->random_colour[0] = COLOUR_RED;
@@ -3327,6 +3333,7 @@ static ChangeInfoResult IndustrytilesChangeInfo(uint indtid, int numinfo, int pr
 
 					tsp->grf_prop.local_id = indtid + i;
 					tsp->grf_prop.subst_id = subs_id;
+					tsp->grf_prop.grfid = _cur.grffile->grfid;
 					tsp->grf_prop.grffile = _cur.grffile;
 					_industile_mngr.AddEntityID(indtid + i, _cur.grffile->grfid, subs_id); // pre-reserve the tile slot
 				}
@@ -3584,6 +3591,7 @@ static ChangeInfoResult IndustriesChangeInfo(uint indid, int numinfo, int prop,
 					indsp->enabled = true;
 					indsp->grf_prop.local_id = indid + i;
 					indsp->grf_prop.subst_id = subs_id;
+					indsp->grf_prop.grfid = _cur.grffile->grfid;
 					indsp->grf_prop.grffile = _cur.grffile;
 					/* If the grf industry needs to check its surrounding upon creation, it should
 					 * rely on callbacks, not on the original placement functions */
@@ -3956,6 +3964,7 @@ static ChangeInfoResult AirportChangeInfo(uint airport, int numinfo, int prop, B
 					as->enabled = true;
 					as->grf_prop.local_id = airport + i;
 					as->grf_prop.subst_id = subs_id;
+					as->grf_prop.grfid = _cur.grffile->grfid;
 					as->grf_prop.grffile = _cur.grffile;
 					/* override the default airport */
 					_airport_mngr.Add(airport + i, _cur.grffile->grfid, subs_id);
@@ -4717,6 +4726,7 @@ static ChangeInfoResult AirportTilesChangeInfo(uint airtid, int numinfo, int pro
 
 					tsp->grf_prop.local_id = airtid + i;
 					tsp->grf_prop.subst_id = subs_id;
+					tsp->grf_prop.grfid = _cur.grffile->grfid;
 					tsp->grf_prop.grffile = _cur.grffile;
 					_airporttile_mngr.AddEntityID(airtid + i, _cur.grffile->grfid, subs_id); // pre-reserve the tile slot
 				}
@@ -5771,12 +5781,13 @@ static void StationMapSpriteGroup(ByteReader &buf, uint8_t idcount)
 			continue;
 		}
 
-		if (statspec->grf_prop.grffile != nullptr) {
+		if (statspec->grf_prop.HasGrfFile()) {
 			GrfMsg(1, "StationMapSpriteGroup: Station {} mapped multiple times, skipping", station);
 			continue;
 		}
 
 		statspec->grf_prop.spritegroup[SpriteGroupCargo::SG_DEFAULT] = _cur.spritegroups[groupid];
+		statspec->grf_prop.grfid = _cur.grffile->grfid;
 		statspec->grf_prop.grffile = _cur.grffile;
 		statspec->grf_prop.local_id = station;
 		StationClass::Assign(statspec);
@@ -5955,12 +5966,13 @@ static void ObjectMapSpriteGroup(ByteReader &buf, uint8_t idcount)
 			continue;
 		}
 
-		if (spec->grf_prop.grffile != nullptr) {
+		if (spec->grf_prop.HasGrfFile()) {
 			GrfMsg(1, "ObjectMapSpriteGroup: Object {} mapped multiple times, skipping", object);
 			continue;
 		}
 
 		spec->grf_prop.spritegroup[OBJECT_SPRITE_GROUP_DEFAULT] = _cur.spritegroups[groupid];
+		spec->grf_prop.grfid = _cur.grffile->grfid;
 		spec->grf_prop.grffile = _cur.grffile;
 		spec->grf_prop.local_id = object;
 	}
@@ -6141,12 +6153,13 @@ static void RoadStopMapSpriteGroup(ByteReader &buf, uint8_t idcount)
 			continue;
 		}
 
-		if (roadstopspec->grf_prop.grffile != nullptr) {
+		if (roadstopspec->grf_prop.HasGrfFile()) {
 			GrfMsg(1, "RoadStopMapSpriteGroup: Road stop {} mapped multiple times, skipping", roadstop);
 			continue;
 		}
 
 		roadstopspec->grf_prop.spritegroup[SpriteGroupCargo::SG_DEFAULT] = _cur.spritegroups[groupid];
+		roadstopspec->grf_prop.grfid = _cur.grffile->grfid;
 		roadstopspec->grf_prop.grffile = _cur.grffile;
 		roadstopspec->grf_prop.local_id = roadstop;
 		RoadStopClass::Assign(roadstopspec);
@@ -9489,25 +9502,25 @@ static void FinaliseIndustriesArray()
 			/* process the conversion of text at the end, so to be sure everything will be fine
 			 * and available.  Check if it does not return undefind marker, which is a very good sign of a
 			 * substitute industry who has not changed the string been examined, thus using it as such */
-			strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->name);
+			strid = GetGRFStringID(indsp->grf_prop.grfid, indsp->name);
 			if (strid != STR_UNDEFINED) indsp->name = strid;
 
-			strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->closure_text);
+			strid = GetGRFStringID(indsp->grf_prop.grfid, indsp->closure_text);
 			if (strid != STR_UNDEFINED) indsp->closure_text = strid;
 
-			strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->production_up_text);
+			strid = GetGRFStringID(indsp->grf_prop.grfid, indsp->production_up_text);
 			if (strid != STR_UNDEFINED) indsp->production_up_text = strid;
 
-			strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->production_down_text);
+			strid = GetGRFStringID(indsp->grf_prop.grfid, indsp->production_down_text);
 			if (strid != STR_UNDEFINED) indsp->production_down_text = strid;
 
-			strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->new_industry_text);
+			strid = GetGRFStringID(indsp->grf_prop.grfid, indsp->new_industry_text);
 			if (strid != STR_UNDEFINED) indsp->new_industry_text = strid;
 
 			if (indsp->station_name != STR_NULL) {
 				/* STR_NULL (0) can be set by grf.  It has a meaning regarding assignation of the
 				 * station's name. Don't want to lose the value, therefore, do not process. */
-				strid = GetGRFStringID(indsp->grf_prop.grffile->grfid, indsp->station_name);
+				strid = GetGRFStringID(indsp->grf_prop.grfid, indsp->station_name);
 				if (strid != STR_UNDEFINED) indsp->station_name = strid;
 			}
 
@@ -9522,9 +9535,9 @@ static void FinaliseIndustriesArray()
 	}
 
 	for (auto &indsp : _industry_specs) {
-		if (indsp.enabled && indsp.grf_prop.grffile != nullptr) {
+		if (indsp.enabled && indsp.grf_prop.HasGrfFile()) {
 			for (auto &conflicting : indsp.conflicting) {
-				conflicting = MapNewGRFIndustryType(conflicting, indsp.grf_prop.grffile->grfid);
+				conflicting = MapNewGRFIndustryType(conflicting, indsp.grf_prop.grfid);
 			}
 		}
 		if (!indsp.enabled) {
@@ -9557,7 +9570,7 @@ static void FinaliseObjectsArray()
 {
 	for (GRFFile * const file : _grf_files) {
 		for (auto &objectspec : file->objectspec) {
-			if (objectspec != nullptr && objectspec->grf_prop.grffile != nullptr && objectspec->IsEnabled()) {
+			if (objectspec != nullptr && objectspec->grf_prop.HasGrfFile() && objectspec->IsEnabled()) {
 				_object_mngr.SetEntitySpec(objectspec.get());
 			}
 		}
diff --git a/src/newgrf_airport.cpp b/src/newgrf_airport.cpp
index 0d90c0adad..e1b974432a 100644
--- a/src/newgrf_airport.cpp
+++ b/src/newgrf_airport.cpp
@@ -132,7 +132,7 @@ void BindAirportSpecs()
 
 void AirportOverrideManager::SetEntitySpec(AirportSpec *as)
 {
-	uint8_t airport_id = this->AddEntityID(as->grf_prop.local_id, as->grf_prop.grffile->grfid, as->grf_prop.subst_id);
+	uint8_t airport_id = this->AddEntityID(as->grf_prop.local_id, as->grf_prop.grfid, as->grf_prop.subst_id);
 
 	if (airport_id == this->invalid_id) {
 		GrfMsg(1, "Airport.SetEntitySpec: Too many airports allocated. Ignoring.");
@@ -145,7 +145,7 @@ void AirportOverrideManager::SetEntitySpec(AirportSpec *as)
 	for (int i = 0; i < this->max_offset; i++) {
 		AirportSpec *overridden_as = AirportSpec::GetWithoutOverride(i);
 
-		if (this->entity_overrides[i] != as->grf_prop.local_id || this->grfid_overrides[i] != as->grf_prop.grffile->grfid) continue;
+		if (this->entity_overrides[i] != as->grf_prop.local_id || this->grfid_overrides[i] != as->grf_prop.grfid) continue;
 
 		overridden_as->grf_prop.override = airport_id;
 		overridden_as->enabled = false;
@@ -277,9 +277,9 @@ StringID GetAirportTextCallback(const AirportSpec *as, uint8_t layout, uint16_t
 	uint16_t cb_res = object.ResolveCallback();
 	if (cb_res == CALLBACK_FAILED || cb_res == 0x400) return STR_UNDEFINED;
 	if (cb_res > 0x400) {
-		ErrorUnknownCallbackResult(as->grf_prop.grffile->grfid, callback, cb_res);
+		ErrorUnknownCallbackResult(as->grf_prop.grfid, callback, cb_res);
 		return STR_UNDEFINED;
 	}
 
-	return GetGRFStringID(as->grf_prop.grffile->grfid, 0xD000 + cb_res);
+	return GetGRFStringID(as->grf_prop.grfid, 0xD000 + cb_res);
 }
diff --git a/src/newgrf_airporttiles.cpp b/src/newgrf_airporttiles.cpp
index 8cd6123182..a5c28ec502 100644
--- a/src/newgrf_airporttiles.cpp
+++ b/src/newgrf_airporttiles.cpp
@@ -66,7 +66,7 @@ void AirportTileSpec::ResetAirportTiles()
 
 void AirportTileOverrideManager::SetEntitySpec(const AirportTileSpec *airpts)
 {
-	StationGfx airpt_id = this->AddEntityID(airpts->grf_prop.local_id, airpts->grf_prop.grffile->grfid, airpts->grf_prop.subst_id);
+	StationGfx airpt_id = this->AddEntityID(airpts->grf_prop.local_id, airpts->grf_prop.grfid, airpts->grf_prop.subst_id);
 
 	if (airpt_id == this->invalid_id) {
 		GrfMsg(1, "AirportTile.SetEntitySpec: Too many airport tiles allocated. Ignoring.");
@@ -79,7 +79,7 @@ void AirportTileOverrideManager::SetEntitySpec(const AirportTileSpec *airpts)
 	for (int i = 0; i < this->max_offset; i++) {
 		AirportTileSpec *overridden_airpts = &AirportTileSpec::tiles[i];
 
-		if (this->entity_overrides[i] != airpts->grf_prop.local_id || this->grfid_overrides[i] != airpts->grf_prop.grffile->grfid) continue;
+		if (this->entity_overrides[i] != airpts->grf_prop.local_id || this->grfid_overrides[i] != airpts->grf_prop.grfid) continue;
 
 		overridden_airpts->grf_prop.override = airpt_id;
 		overridden_airpts->enabled = false;
@@ -141,7 +141,7 @@ static uint32_t GetAirportTileIDAtOffset(TileIndex tile, const Station *st, uint
 		/* Overridden */
 		const AirportTileSpec *tile_ovr = AirportTileSpec::Get(ats->grf_prop.override);
 
-		if (tile_ovr->grf_prop.grffile->grfid == cur_grfid) {
+		if (tile_ovr->grf_prop.grfid == cur_grfid) {
 			return tile_ovr->grf_prop.local_id; // same grf file
 		} else {
 			return 0xFFFE; // not the same grf file
@@ -149,7 +149,7 @@ static uint32_t GetAirportTileIDAtOffset(TileIndex tile, const Station *st, uint
 	}
 	/* Not an 'old type' tile */
 	if (ats->grf_prop.spritegroup[0] != nullptr) { // tile has a spritegroup ?
-		if (ats->grf_prop.grffile->grfid == cur_grfid) { // same airport, same grf ?
+		if (ats->grf_prop.grfid == cur_grfid) { // same airport, same grf ?
 			return ats->grf_prop.local_id;
 		} else {
 			return 0xFFFE; // Defined in another grf file
diff --git a/src/newgrf_animation_base.h b/src/newgrf_animation_base.h
index ab919e2e84..3352f7705a 100644
--- a/src/newgrf_animation_base.h
+++ b/src/newgrf_animation_base.h
@@ -58,7 +58,7 @@ struct AnimationBase {
 		if (HasBit(spec->callback_mask, Tbase::cbm_animation_speed)) {
 			uint16_t callback = GetCallback(Tbase::cb_animation_speed, 0, 0, spec, obj, tile, extra_data);
 			if (callback != CALLBACK_FAILED) {
-				if (callback >= 0x100 && spec->grf_prop.grffile->grf_version >= 8) ErrorUnknownCallbackResult(spec->grf_prop.grffile->grfid, Tbase::cb_animation_speed, callback);
+				if (callback >= 0x100 && spec->grf_prop.grffile->grf_version >= 8) ErrorUnknownCallbackResult(spec->grf_prop.grfid, Tbase::cb_animation_speed, callback);
 				animation_speed = Clamp(callback & 0xFF, 0, 16);
 			}
 		}
diff --git a/src/newgrf_class_func.h b/src/newgrf_class_func.h
index 57c2dda438..783bb99a3d 100644
--- a/src/newgrf_class_func.h
+++ b/src/newgrf_class_func.h
@@ -131,7 +131,7 @@ const Tspec *NewGRFClass<Tspec, Tindex, Tmax>::GetByGrf(uint32_t grfid, uint16_t
 		for (const auto &spec : cls.spec) {
 			if (spec == nullptr) continue;
 			if (spec->grf_prop.local_id != local_id) continue;
-			if ((spec->grf_prop.grffile == nullptr ? 0 : spec->grf_prop.grffile->grfid) == grfid) return spec;
+			if (spec->grf_prop.grfid == grfid) return spec;
 		}
 	}
 
diff --git a/src/newgrf_commons.cpp b/src/newgrf_commons.cpp
index 822b641cbe..e9298790b8 100644
--- a/src/newgrf_commons.cpp
+++ b/src/newgrf_commons.cpp
@@ -158,7 +158,7 @@ uint16_t OverrideManagerBase::GetSubstituteID(uint16_t entity_id) const
  */
 void HouseOverrideManager::SetEntitySpec(const HouseSpec *hs)
 {
-	HouseID house_id = this->AddEntityID(hs->grf_prop.local_id, hs->grf_prop.grffile->grfid, hs->grf_prop.subst_id);
+	HouseID house_id = this->AddEntityID(hs->grf_prop.local_id, hs->grf_prop.grfid, hs->grf_prop.subst_id);
 
 	if (house_id == this->invalid_id) {
 		GrfMsg(1, "House.SetEntitySpec: Too many houses allocated. Ignoring.");
@@ -175,7 +175,7 @@ void HouseOverrideManager::SetEntitySpec(const HouseSpec *hs)
 	for (int i = 0; i < this->max_offset; i++) {
 		HouseSpec *overridden_hs = HouseSpec::Get(i);
 
-		if (this->entity_overrides[i] != hs->grf_prop.local_id || this->grfid_overrides[i] != hs->grf_prop.grffile->grfid) continue;
+		if (this->entity_overrides[i] != hs->grf_prop.local_id || this->grfid_overrides[i] != hs->grf_prop.grfid) continue;
 
 		overridden_hs->grf_prop.override = house_id;
 		this->entity_overrides[i] = this->invalid_id;
@@ -222,7 +222,7 @@ uint16_t IndustryOverrideManager::AddEntityID(uint16_t grf_local_id, uint32_t gr
 		/* This industry must be one that is not available(enabled), mostly because of climate.
 		 * And it must not already be used by a grf (grffile == nullptr).
 		 * So reserve this slot here, as it is the chosen one */
-		if (!inds->enabled && inds->grf_prop.grffile == nullptr) {
+		if (!inds->enabled && !inds->grf_prop.HasGrfFile()) {
 			EntityIDMapping *map = &this->mappings[id];
 
 			if (map->entity_id == 0 && map->grfid == 0) {
@@ -247,14 +247,14 @@ uint16_t IndustryOverrideManager::AddEntityID(uint16_t grf_local_id, uint32_t gr
 void IndustryOverrideManager::SetEntitySpec(IndustrySpec *inds)
 {
 	/* First step : We need to find if this industry is already specified in the savegame data. */
-	IndustryType ind_id = this->GetID(inds->grf_prop.local_id, inds->grf_prop.grffile->grfid);
+	IndustryType ind_id = this->GetID(inds->grf_prop.local_id, inds->grf_prop.grfid);
 
 	if (ind_id == this->invalid_id) {
 		/* Not found.
 		 * Or it has already been overridden, so you've lost your place.
 		 * Or it is a simple substitute.
 		 * We need to find a free available slot */
-		ind_id = this->AddEntityID(inds->grf_prop.local_id, inds->grf_prop.grffile->grfid, inds->grf_prop.subst_id);
+		ind_id = this->AddEntityID(inds->grf_prop.local_id, inds->grf_prop.grfid, inds->grf_prop.subst_id);
 		inds->grf_prop.override = this->invalid_id;  // make sure it will not be detected as overridden
 	}
 
@@ -271,7 +271,7 @@ void IndustryOverrideManager::SetEntitySpec(IndustrySpec *inds)
 
 void IndustryTileOverrideManager::SetEntitySpec(const IndustryTileSpec *its)
 {
-	IndustryGfx indt_id = this->AddEntityID(its->grf_prop.local_id, its->grf_prop.grffile->grfid, its->grf_prop.subst_id);
+	IndustryGfx indt_id = this->AddEntityID(its->grf_prop.local_id, its->grf_prop.grfid, its->grf_prop.subst_id);
 
 	if (indt_id == this->invalid_id) {
 		GrfMsg(1, "IndustryTile.SetEntitySpec: Too many industry tiles allocated. Ignoring.");
@@ -284,7 +284,7 @@ void IndustryTileOverrideManager::SetEntitySpec(const IndustryTileSpec *its)
 	for (int i = 0; i < this->max_offset; i++) {
 		IndustryTileSpec *overridden_its = &_industry_tile_specs[i];
 
-		if (this->entity_overrides[i] != its->grf_prop.local_id || this->grfid_overrides[i] != its->grf_prop.grffile->grfid) continue;
+		if (this->entity_overrides[i] != its->grf_prop.local_id || this->grfid_overrides[i] != its->grf_prop.grfid) continue;
 
 		overridden_its->grf_prop.override = indt_id;
 		overridden_its->enabled = false;
@@ -302,14 +302,14 @@ void IndustryTileOverrideManager::SetEntitySpec(const IndustryTileSpec *its)
 void ObjectOverrideManager::SetEntitySpec(ObjectSpec *spec)
 {
 	/* First step : We need to find if this object is already specified in the savegame data. */
-	ObjectType type = this->GetID(spec->grf_prop.local_id, spec->grf_prop.grffile->grfid);
+	ObjectType type = this->GetID(spec->grf_prop.local_id, spec->grf_prop.grfid);
 
 	if (type == this->invalid_id) {
 		/* Not found.
 		 * Or it has already been overridden, so you've lost your place.
 		 * Or it is a simple substitute.
 		 * We need to find a free available slot */
-		type = this->AddEntityID(spec->grf_prop.local_id, spec->grf_prop.grffile->grfid, OBJECT_TRANSMITTER);
+		type = this->AddEntityID(spec->grf_prop.local_id, spec->grf_prop.grfid, OBJECT_TRANSMITTER);
 	}
 
 	if (type == this->invalid_id) {
diff --git a/src/newgrf_commons.h b/src/newgrf_commons.h
index a45fcdf592..0c82254e80 100644
--- a/src/newgrf_commons.h
+++ b/src/newgrf_commons.h
@@ -309,8 +309,15 @@ bool Convert8bitBooleanCallback(const struct GRFFile *grffile, uint16_t cbid, ui
 template <size_t Tcnt>
 struct GRFFilePropsBase {
 	uint16_t local_id = 0; ///< id defined by the grf file for this entity
+	uint32_t grfid = 0; ///< grfid that introduced this entity.
 	const struct GRFFile *grffile = nullptr; ///< grf file that introduced this entity
 	std::array<const struct SpriteGroup *, Tcnt> spritegroup{}; ///< pointers to the different sprites of the entity
+
+	/**
+	 * Test if this entity was introduced by NewGRF.
+	 * @returns true iff the grfid property is set.
+	 */
+	inline bool HasGrfFile() const { return this->grffile != nullptr; }
 };
 
 /** Data related to the handling of grf files. */
diff --git a/src/newgrf_engine.cpp b/src/newgrf_engine.cpp
index 73713c9cce..f74f53dda4 100644
--- a/src/newgrf_engine.cpp
+++ b/src/newgrf_engine.cpp
@@ -71,6 +71,7 @@ void SetCustomEngineSprites(EngineID engine, uint8_t cargo, const SpriteGroup *g
 void SetEngineGRF(EngineID engine, const GRFFile *file)
 {
 	Engine *e = Engine::Get(engine);
+	e->grf_prop.grfid = file->grfid;
 	e->grf_prop.grffile = file;
 }
 
diff --git a/src/newgrf_house.cpp b/src/newgrf_house.cpp
index ee166c84ff..b87aaa63a5 100644
--- a/src/newgrf_house.cpp
+++ b/src/newgrf_house.cpp
@@ -273,14 +273,14 @@ static bool SearchNearbyHouseID(TileIndex tile, void *user_data)
 	if (IsTileType(tile, MP_HOUSE)) {
 		HouseID house = GetHouseType(tile); // tile been examined
 		const HouseSpec *hs = HouseSpec::Get(house);
-		if (hs->grf_prop.grffile != nullptr) { // must be one from a grf file
+		if (hs->grf_prop.HasGrfFile()) { // must be one from a grf file
 			SearchNearbyHouseData *nbhd = (SearchNearbyHouseData *)user_data;
 
 			TileIndex north_tile = tile + GetHouseNorthPart(house); // modifies 'house'!
 			if (north_tile == nbhd->north_tile) return false; // Always ignore origin house
 
 			return hs->grf_prop.local_id == nbhd->hs->grf_prop.local_id &&  // same local id as the one requested
-				hs->grf_prop.grffile->grfid == nbhd->hs->grf_prop.grffile->grfid;  // from the same grf
+				hs->grf_prop.grfid == nbhd->hs->grf_prop.grfid;  // from the same grf
 		}
 	}
 	return false;
@@ -297,14 +297,14 @@ static bool SearchNearbyHouseClass(TileIndex tile, void *user_data)
 	if (IsTileType(tile, MP_HOUSE)) {
 		HouseID house = GetHouseType(tile); // tile been examined
 		const HouseSpec *hs = HouseSpec::Get(house);
-		if (hs->grf_prop.grffile != nullptr) { // must be one from a grf file
+		if (hs->grf_prop.HasGrfFile()) { // must be one from a grf file
 			SearchNearbyHouseData *nbhd = (SearchNearbyHouseData *)user_data;
 
 			TileIndex north_tile = tile + GetHouseNorthPart(house); // modifies 'house'!
 			if (north_tile == nbhd->north_tile) return false; // Always ignore origin house
 
 			return hs->class_id == nbhd->hs->class_id &&  // same classid as the one requested
-				hs->grf_prop.grffile->grfid == nbhd->hs->grf_prop.grffile->grfid;  // from the same grf
+				hs->grf_prop.grfid == nbhd->hs->grf_prop.grfid;  // from the same grf
 		}
 	}
 	return false;
@@ -321,13 +321,13 @@ static bool SearchNearbyHouseGRFID(TileIndex tile, void *user_data)
 	if (IsTileType(tile, MP_HOUSE)) {
 		HouseID house = GetHouseType(tile); // tile been examined
 		const HouseSpec *hs = HouseSpec::Get(house);
-		if (hs->grf_prop.grffile != nullptr) { // must be one from a grf file
+		if (hs->grf_prop.HasGrfFile()) { // must be one from a grf file
 			SearchNearbyHouseData *nbhd = (SearchNearbyHouseData *)user_data;
 
 			TileIndex north_tile = tile + GetHouseNorthPart(house); // modifies 'house'!
 			if (north_tile == nbhd->north_tile) return false; // Always ignore origin house
 
-			return hs->grf_prop.grffile->grfid == nbhd->hs->grf_prop.grffile->grfid;  // from the same grf
+			return hs->grf_prop.grfid == nbhd->hs->grf_prop.grfid;  // from the same grf
 		}
 	}
 	return false;
@@ -429,9 +429,9 @@ static uint32_t GetDistanceFromNearbyHouse(uint8_t parameter, TileIndex tile, Ho
 		/* Building counts for new houses with id = parameter. */
 		case 0x61: {
 			const HouseSpec *hs = HouseSpec::Get(this->house_id);
-			if (hs->grf_prop.grffile == nullptr) return 0;
+			if (!hs->grf_prop.HasGrfFile()) return 0;
 
-			HouseID new_house = _house_mngr.GetID(parameter, hs->grf_prop.grffile->grfid);
+			HouseID new_house = _house_mngr.GetID(parameter, hs->grf_prop.grfid);
 			return new_house == INVALID_HOUSE_ID ? 0 : GetNumHouses(new_house, this->town);
 		}
 
diff --git a/src/newgrf_industries.cpp b/src/newgrf_industries.cpp
index 221c224922..0fcb9dcde7 100644
--- a/src/newgrf_industries.cpp
+++ b/src/newgrf_industries.cpp
@@ -71,7 +71,7 @@ uint32_t GetIndustryIDAtOffset(TileIndex tile, const Industry *i, uint32_t cur_g
 		/* Overridden */
 		const IndustryTileSpec *tile_ovr = GetIndustryTileSpec(indtsp->grf_prop.override);
 
-		if (tile_ovr->grf_prop.grffile->grfid == cur_grfid) {
+		if (tile_ovr->grf_prop.grfid == cur_grfid) {
 			return tile_ovr->grf_prop.local_id; // same grf file
 		} else {
 			return 0xFFFE; // not the same grf file
@@ -79,7 +79,7 @@ uint32_t GetIndustryIDAtOffset(TileIndex tile, const Industry *i, uint32_t cur_g
 	}
 	/* Not an 'old type' tile */
 	if (indtsp->grf_prop.spritegroup[0] != nullptr) { // tile has a spritegroup ?
-		if (indtsp->grf_prop.grffile->grfid == cur_grfid) { // same industry, same grf ?
+		if (indtsp->grf_prop.grfid == cur_grfid) { // same industry, same grf ?
 			return indtsp->grf_prop.local_id;
 		} else {
 			return 0xFFFE; // Defined in another grf file
@@ -126,7 +126,7 @@ static uint32_t GetCountAndDistanceOfClosestInstance(uint8_t param_setID, uint8_
 			break;
 
 		case 0xFFFFFFFF: // current grf
-			GrfID = GetIndustrySpec(current->type)->grf_prop.grffile->grfid;
+			GrfID = GetIndustrySpec(current->type)->grf_prop.grfid;
 			[[fallthrough]];
 
 		default: // use the grfid specified in register 100h
@@ -284,7 +284,7 @@ static uint32_t GetCountAndDistanceOfClosestInstance(uint8_t param_setID, uint8_
 		/* Distance of nearest industry of given type */
 		case 0x64: {
 			if (this->tile == INVALID_TILE) break;
-			IndustryType type = MapNewGRFIndustryType(parameter, indspec->grf_prop.grffile->grfid);
+			IndustryType type = MapNewGRFIndustryType(parameter, indspec->grf_prop.grfid);
 			if (type >= NUM_INDUSTRYTYPES) return UINT32_MAX;
 			return GetClosestIndustry(this->tile, type, this->industry);
 		}
@@ -443,9 +443,8 @@ static uint32_t GetCountAndDistanceOfClosestInstance(uint8_t param_setID, uint8_
 
 		/* Create storage on first modification. */
 		const IndustrySpec *indsp = GetIndustrySpec(this->industry->type);
-		uint32_t grfid = (indsp->grf_prop.grffile != nullptr) ? indsp->grf_prop.grffile->grfid : 0;
 		assert(PersistentStorage::CanAllocateItem());
-		this->industry->psa = new PersistentStorage(grfid, GSF_INDUSTRIES, this->industry->location.tile);
+		this->industry->psa = new PersistentStorage(indsp->grf_prop.grfid, GSF_INDUSTRIES, this->industry->location.tile);
 	}
 
 	this->industry->psa->StoreValue(pos, value);
@@ -584,7 +583,7 @@ uint32_t GetIndustryProbabilityCallback(IndustryType type, IndustryAvailabilityC
 				if (res < 0x100) {
 					default_prob = res;
 				} else if (res > 0x100) {
-					ErrorUnknownCallbackResult(indspec->grf_prop.grffile->grfid, CBID_INDUSTRY_PROBABILITY, res);
+					ErrorUnknownCallbackResult(indspec->grf_prop.grfid, CBID_INDUSTRY_PROBABILITY, res);
 				}
 			}
 		}
diff --git a/src/newgrf_object.cpp b/src/newgrf_object.cpp
index 14046a469b..832f9769ae 100644
--- a/src/newgrf_object.cpp
+++ b/src/newgrf_object.cpp
@@ -173,11 +173,11 @@ static uint32_t GetObjectIDAtOffset(TileIndex tile, uint32_t cur_grfid)
 	const ObjectSpec *spec = ObjectSpec::Get(o->type);
 
 	/* Default objects have no associated NewGRF file */
-	if (spec->grf_prop.grffile == nullptr) {
+	if (!spec->grf_prop.HasGrfFile()) {
 		return 0xFFFE; // Defined in another grf file
 	}
 
-	if (spec->grf_prop.grffile->grfid == cur_grfid) { // same object, same grf ?
+	if (spec->grf_prop.grfid == cur_grfid) { // same object, same grf ?
 		return spec->grf_prop.local_id | o->view << 16;
 	}
 
diff --git a/src/newgrf_roadstop.cpp b/src/newgrf_roadstop.cpp
index 66c818c5f1..b2d949b6fc 100644
--- a/src/newgrf_roadstop.cpp
+++ b/src/newgrf_roadstop.cpp
@@ -570,7 +570,7 @@ int AllocateSpecToRoadStop(const RoadStopSpec *statspec, BaseStation *st, bool e
 	if (exec) {
 		if (i >= st->roadstop_speclist.size()) st->roadstop_speclist.resize(i + 1);
 		st->roadstop_speclist[i].spec     = statspec;
-		st->roadstop_speclist[i].grfid    = statspec->grf_prop.grffile->grfid;
+		st->roadstop_speclist[i].grfid    = statspec->grf_prop.grfid;
 		st->roadstop_speclist[i].localidx = statspec->grf_prop.local_id;
 
 		RoadStopUpdateCachedTriggers(st);
diff --git a/src/newgrf_station.cpp b/src/newgrf_station.cpp
index 86dbe8bf32..a1caf62e40 100644
--- a/src/newgrf_station.cpp
+++ b/src/newgrf_station.cpp
@@ -708,7 +708,7 @@ int AllocateSpecToStation(const StationSpec *statspec, BaseStation *st, bool exe
 	if (exec) {
 		if (i >= st->speclist.size()) st->speclist.resize(i + 1);
 		st->speclist[i].spec     = statspec;
-		st->speclist[i].grfid    = statspec->grf_prop.grffile->grfid;
+		st->speclist[i].grfid    = statspec->grf_prop.grfid;
 		st->speclist[i].localidx = statspec->grf_prop.local_id;
 
 		StationUpdateCachedTriggers(st);
diff --git a/src/object_cmd.cpp b/src/object_cmd.cpp
index 3c7bfa1432..5338fe5036 100644
--- a/src/object_cmd.cpp
+++ b/src/object_cmd.cpp
@@ -112,7 +112,7 @@ void BuildObject(ObjectType type, TileIndex tile, CompanyID owner, Town *town, u
 	if (HasBit(spec->callback_mask, CBM_OBJ_COLOUR)) {
 		uint16_t res = GetObjectCallback(CBID_OBJECT_COLOUR, o->colour, 0, spec, o, tile);
 		if (res != CALLBACK_FAILED) {
-			if (res >= 0x100) ErrorUnknownCallbackResult(spec->grf_prop.grffile->grfid, CBID_OBJECT_COLOUR, res);
+			if (res >= 0x100) ErrorUnknownCallbackResult(spec->grf_prop.grfid, CBID_OBJECT_COLOUR, res);
 			o->colour = GB(res, 0, 8);
 		}
 	}
@@ -665,8 +665,8 @@ static void GetTileDesc_Object(TileIndex tile, TileDesc *td)
 	td->owner[0] = GetTileOwner(tile);
 	td->build_date = Object::GetByTile(tile)->build_date;
 
-	if (spec->grf_prop.grffile != nullptr) {
-		td->grf = GetGRFConfig(spec->grf_prop.grffile->grfid)->GetName();
+	if (spec->grf_prop.HasGrfFile()) {
+		td->grf = GetGRFConfig(spec->grf_prop.grfid)->GetName();
 	}
 }
 
diff --git a/src/object_gui.cpp b/src/object_gui.cpp
index 8bc2e98d4c..59003e1928 100644
--- a/src/object_gui.cpp
+++ b/src/object_gui.cpp
@@ -86,7 +86,7 @@ public:
 	void DrawType(int x, int y, int cls_id, int id) const override
 	{
 		const auto *spec = this->GetSpec(cls_id, id);
-		if (spec->grf_prop.grffile == nullptr) {
+		if (!spec->grf_prop.HasGrfFile()) {
 			extern const DrawTileSprites _objects[];
 			const DrawTileSprites *dts = &_objects[spec->grf_prop.local_id];
 			DrawOrigTileSeqInGUI(x, y, dts, PAL_NONE);
@@ -207,7 +207,7 @@ public:
 					int x = (ir.Width()  - ScaleSpriteTrad(PREVIEW_WIDTH)) / 2 + ScaleSpriteTrad(PREVIEW_LEFT);
 					int y = (ir.Height() + ScaleSpriteTrad(PREVIEW_HEIGHT)) / 2 - ScaleSpriteTrad(PREVIEW_BOTTOM);
 
-					if (spec->grf_prop.grffile == nullptr) {
+					if (!spec->grf_prop.HasGrfFile()) {
 						extern const DrawTileSprites _objects[];
 						const DrawTileSprites *dts = &_objects[spec->grf_prop.local_id];
 						DrawOrigTileSeqInGUI(x, y, dts, PAL_NONE);
@@ -228,9 +228,9 @@ public:
 					uint16_t callback_res = GetObjectCallback(CBID_OBJECT_FUND_MORE_TEXT, 0, 0, spec, nullptr, INVALID_TILE, _object_gui.sel_view);
 					if (callback_res != CALLBACK_FAILED && callback_res != 0x400) {
 						if (callback_res > 0x400) {
-							ErrorUnknownCallbackResult(spec->grf_prop.grffile->grfid, CBID_OBJECT_FUND_MORE_TEXT, callback_res);
+							ErrorUnknownCallbackResult(spec->grf_prop.grfid, CBID_OBJECT_FUND_MORE_TEXT, callback_res);
 						} else {
-							StringID message = GetGRFStringID(spec->grf_prop.grffile->grfid, 0xD000 + callback_res);
+							StringID message = GetGRFStringID(spec->grf_prop.grfid, 0xD000 + callback_res);
 							if (message != STR_NULL && message != STR_UNDEFINED) {
 								StartTextRefStackUsage(spec->grf_prop.grffile, 6);
 								/* Use all the available space left from where we stand up to the
diff --git a/src/picker_gui.h b/src/picker_gui.h
index 3ff9e2f314..41fbd48f03 100644
--- a/src/picker_gui.h
+++ b/src/picker_gui.h
@@ -113,7 +113,7 @@ public:
 	PickerItem GetPickerItem(const typename T::spec_type *spec, int cls_id = -1, int id = -1) const
 	{
 		if (spec == nullptr) return {0, 0, cls_id, id};
-		return {spec->grf_prop.grffile == nullptr ? 0 : spec->grf_prop.grffile->grfid, spec->grf_prop.local_id, spec->class_index, spec->index};
+		return {spec->grf_prop.grfid, spec->grf_prop.local_id, spec->class_index, spec->index};
 	}
 
 	PickerItem GetPickerItem(int cls_id, int id) const override
diff --git a/src/saveload/waypoint_sl.cpp b/src/saveload/waypoint_sl.cpp
index 733561a58d..fdce9cb265 100644
--- a/src/saveload/waypoint_sl.cpp
+++ b/src/saveload/waypoint_sl.cpp
@@ -87,7 +87,7 @@ void MoveWaypointsToBaseStations()
 		 * from the GRF ID / station index. */
 		for (OldWaypoint &wp : _old_waypoints) {
 			const auto specs = StationClass::Get(STAT_CLASS_WAYP)->Specs();
-			auto found = std::ranges::find_if(specs, [&wp](const StationSpec *spec) { return spec != nullptr && spec->grf_prop.grffile->grfid == wp.grfid && spec->grf_prop.local_id == wp.localidx; });
+			auto found = std::ranges::find_if(specs, [&wp](const StationSpec *spec) { return spec != nullptr && spec->grf_prop.grfid == wp.grfid && spec->grf_prop.local_id == wp.localidx; });
 			if (found != std::end(specs)) wp.spec = *found;
 		}
 	}
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
index 7dac954c89..8a49d61864 100644
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -1479,7 +1479,7 @@ CommandCost CmdBuildRailStation(DoCommandFlag flags, TileIndex tile_org, RailTyp
 						if (callback <= UINT8_MAX) {
 							SetStationGfx(tile, (callback & ~1) + axis);
 						} else {
-							ErrorUnknownCallbackResult(statspec->grf_prop.grffile->grfid, CBID_STATION_BUILD_TILE_LAYOUT, callback);
+							ErrorUnknownCallbackResult(statspec->grf_prop.grfid, CBID_STATION_BUILD_TILE_LAYOUT, callback);
 						}
 					}
 
@@ -3503,8 +3503,8 @@ void FillTileDescRailStation(TileIndex tile, TileDesc *td)
 		td->station_class = StationClass::Get(spec->class_index)->name;
 		td->station_name  = spec->name;
 
-		if (spec->grf_prop.grffile != nullptr) {
-			const GRFConfig *gc = GetGRFConfig(spec->grf_prop.grffile->grfid);
+		if (spec->grf_prop.HasGrfFile()) {
+			const GRFConfig *gc = GetGRFConfig(spec->grf_prop.grfid);
 			td->grf = gc->GetName();
 		}
 	}
@@ -3523,11 +3523,11 @@ void FillTileDescAirport(TileIndex tile, TileDesc *td)
 	const AirportTileSpec *ats = AirportTileSpec::GetByTile(tile);
 	td->airport_tile_name = ats->name;
 
-	if (as->grf_prop.grffile != nullptr) {
-		const GRFConfig *gc = GetGRFConfig(as->grf_prop.grffile->grfid);
+	if (as->grf_prop.HasGrfFile()) {
+		const GRFConfig *gc = GetGRFConfig(as->grf_prop.grfid);
 		td->grf = gc->GetName();
-	} else if (ats->grf_prop.grffile != nullptr) {
-		const GRFConfig *gc = GetGRFConfig(ats->grf_prop.grffile->grfid);
+	} else if (ats->grf_prop.HasGrfFile()) {
+		const GRFConfig *gc = GetGRFConfig(ats->grf_prop.grfid);
 		td->grf = gc->GetName();
 	}
 }
@@ -3555,7 +3555,7 @@ static void GetTileDesc_Station(TileIndex tile, TileDesc *td)
 			const IndustrySpec *is = GetIndustrySpec(i->type);
 			td->owner[0] = i->owner;
 			str = is->name;
-			if (is->grf_prop.grffile != nullptr) td->grf = GetGRFConfig(is->grf_prop.grffile->grfid)->GetName();
+			if (is->grf_prop.HasGrfFile()) td->grf = GetGRFConfig(is->grf_prop.grfid)->GetName();
 			break;
 		}
 		case STATION_DOCK:     str = STR_LAI_STATION_DESCRIPTION_SHIP_DOCK; break;
diff --git a/src/table/newgrf_debug_data.h b/src/table/newgrf_debug_data.h
index 6f4f9eb486..aa4b4e9ba6 100644
--- a/src/table/newgrf_debug_data.h
+++ b/src/table/newgrf_debug_data.h
@@ -141,7 +141,7 @@ class NIHStation : public NIHelper {
 	const void *GetInstance(uint ) const override        { return nullptr; }
 	const void *GetSpec(uint index) const override       { return GetStationSpec(index); }
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_STATION_NAME, GetStationIndex(index), index); }
-	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetStationSpec(index)->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetStationSpec(index)->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint param, bool &avail) const override
 	{
@@ -201,12 +201,12 @@ static const NIVariable _niv_house[] = {
 };
 
 class NIHHouse : public NIHelper {
-	bool IsInspectable(uint index) const override        { return HouseSpec::Get(GetHouseType(index))->grf_prop.grffile != nullptr; }
+	bool IsInspectable(uint index) const override        { return HouseSpec::Get(GetHouseType(index))->grf_prop.HasGrfFile(); }
 	uint GetParent(uint index) const override            { return GetInspectWindowNumber(GSF_FAKE_TOWNS, GetTownIndex(index)); }
 	const void *GetInstance(uint)const override          { return nullptr; }
 	const void *GetSpec(uint index) const override       { return HouseSpec::Get(GetHouseType(index)); }
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_TOWN_NAME, GetTownIndex(index), index); }
-	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? HouseSpec::Get(GetHouseType(index))->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? HouseSpec::Get(GetHouseType(index))->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint param, bool &avail) const override
 	{
@@ -251,12 +251,12 @@ static const NIVariable _niv_industrytiles[] = {
 };
 
 class NIHIndustryTile : public NIHelper {
-	bool IsInspectable(uint index) const override        { return GetIndustryTileSpec(GetIndustryGfx(index))->grf_prop.grffile != nullptr; }
+	bool IsInspectable(uint index) const override        { return GetIndustryTileSpec(GetIndustryGfx(index))->grf_prop.HasGrfFile(); }
 	uint GetParent(uint index) const override            { return GetInspectWindowNumber(GSF_INDUSTRIES, GetIndustryIndex(index)); }
 	const void *GetInstance(uint)const override          { return nullptr; }
 	const void *GetSpec(uint index) const override       { return GetIndustryTileSpec(GetIndustryGfx(index)); }
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_INDUSTRY_NAME, GetIndustryIndex(index), index); }
-	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetIndustryTileSpec(GetIndustryGfx(index))->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetIndustryTileSpec(GetIndustryGfx(index))->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint param, bool &avail) const override
 	{
@@ -364,12 +364,12 @@ static const NIVariable _niv_industries[] = {
 };
 
 class NIHIndustry : public NIHelper {
-	bool IsInspectable(uint index) const override        { return GetIndustrySpec(Industry::Get(index)->type)->grf_prop.grffile != nullptr; }
+	bool IsInspectable(uint index) const override        { return GetIndustrySpec(Industry::Get(index)->type)->grf_prop.HasGrfFile(); }
 	uint GetParent(uint index) const override            { return GetInspectWindowNumber(GSF_FAKE_TOWNS, Industry::Get(index)->town->index); }
 	const void *GetInstance(uint index)const override    { return Industry::Get(index); }
 	const void *GetSpec(uint index) const override       { return GetIndustrySpec(Industry::Get(index)->type); }
 	void SetStringParameters(uint index) const override  { this->SetSimpleStringParameters(STR_INDUSTRY_NAME, index); }
-	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetIndustrySpec(Industry::Get(index)->type)->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetIndustrySpec(Industry::Get(index)->type)->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint param, bool &avail) const override
 	{
@@ -427,12 +427,12 @@ static const NIVariable _niv_objects[] = {
 };
 
 class NIHObject : public NIHelper {
-	bool IsInspectable(uint index) const override        { return ObjectSpec::GetByTile(index)->grf_prop.grffile != nullptr; }
+	bool IsInspectable(uint index) const override        { return ObjectSpec::GetByTile(index)->grf_prop.HasGrfFile(); }
 	uint GetParent(uint index) const override            { return GetInspectWindowNumber(GSF_FAKE_TOWNS, Object::GetByTile(index)->town->index); }
 	const void *GetInstance(uint index)const override    { return Object::GetByTile(index); }
 	const void *GetSpec(uint index) const override       { return ObjectSpec::GetByTile(index); }
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_NEWGRF_INSPECT_CAPTION_OBJECT_AT_OBJECT, INVALID_STRING_ID, index); }
-	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? ObjectSpec::GetByTile(index)->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? ObjectSpec::GetByTile(index)->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint param, bool &avail) const override
 	{
@@ -497,12 +497,12 @@ static const NICallback _nic_airporttiles[] = {
 };
 
 class NIHAirportTile : public NIHelper {
-	bool IsInspectable(uint index) const override        { return AirportTileSpec::Get(GetAirportGfx(index))->grf_prop.grffile != nullptr; }
+	bool IsInspectable(uint index) const override        { return AirportTileSpec::Get(GetAirportGfx(index))->grf_prop.HasGrfFile(); }
 	uint GetParent(uint index) const override            { return GetInspectWindowNumber(GSF_AIRPORTS, GetStationIndex(index)); }
 	const void *GetInstance(uint)const override          { return nullptr; }
 	const void *GetSpec(uint index) const override       { return AirportTileSpec::Get(GetAirportGfx(index)); }
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_STATION_NAME, GetStationIndex(index), index); }
-	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? AirportTileSpec::Get(GetAirportGfx(index))->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? AirportTileSpec::Get(GetAirportGfx(index))->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint param, bool &avail) const override
 	{
@@ -538,12 +538,12 @@ static const NIVariable _niv_airports[] = {
 };
 
 class NIHAirport : public NIHelper {
-	bool IsInspectable(uint index) const override        { return AirportSpec::Get(Station::Get(index)->airport.type)->grf_prop.grffile != nullptr; }
+	bool IsInspectable(uint index) const override        { return AirportSpec::Get(Station::Get(index)->airport.type)->grf_prop.HasGrfFile(); }
 	uint GetParent(uint index) const override            { return GetInspectWindowNumber(GSF_FAKE_TOWNS, Station::Get(index)->town->index); }
 	const void *GetInstance(uint index)const override    { return Station::Get(index); }
 	const void *GetSpec(uint index) const override       { return AirportSpec::Get(Station::Get(index)->airport.type); }
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_STATION_NAME, index, Station::Get(index)->airport.tile); }
-	uint32_t GetGRFID(uint index) const override         { return (this->IsInspectable(index)) ? AirportSpec::Get(Station::Get(index)->airport.type)->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override         { return (this->IsInspectable(index)) ? AirportSpec::Get(Station::Get(index)->airport.type)->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint param, bool &avail) const override
 	{
@@ -700,7 +700,7 @@ class NIHRoadStop : public NIHelper {
 	const void *GetInstance(uint)const override          { return nullptr; }
 	const void *GetSpec(uint index) const override       { return GetRoadStopSpec(index); }
 	void SetStringParameters(uint index) const override  { this->SetObjectAtStringParameters(STR_STATION_NAME, GetStationIndex(index), index); }
-	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetRoadStopSpec(index)->grf_prop.grffile->grfid : 0; }
+	uint32_t GetGRFID(uint index) const override           { return (this->IsInspectable(index)) ? GetRoadStopSpec(index)->grf_prop.grfid : 0; }
 
 	uint Resolve(uint index, uint var, uint32_t param, bool &avail) const override
 	{
diff --git a/src/town_cmd.cpp b/src/town_cmd.cpp
index ae02481c20..1042f3de18 100644
--- a/src/town_cmd.cpp
+++ b/src/town_cmd.cpp
@@ -869,9 +869,9 @@ static void GetTileDesc_Town(TileIndex tile, TileDesc *td)
 	uint16_t callback_res = GetHouseCallback(CBID_HOUSE_CUSTOM_NAME, house_completed ? 1 : 0, 0, house, Town::GetByTile(tile), tile);
 	if (callback_res != CALLBACK_FAILED && callback_res != 0x400) {
 		if (callback_res > 0x400) {
-			ErrorUnknownCallbackResult(hs->grf_prop.grffile->grfid, CBID_HOUSE_CUSTOM_NAME, callback_res);
+			ErrorUnknownCallbackResult(hs->grf_prop.grfid, CBID_HOUSE_CUSTOM_NAME, callback_res);
 		} else {
-			StringID new_name = GetGRFStringID(hs->grf_prop.grffile->grfid, 0xD000 + callback_res);
+			StringID new_name = GetGRFStringID(hs->grf_prop.grfid, 0xD000 + callback_res);
 			if (new_name != STR_NULL && new_name != STR_UNDEFINED) {
 				td->str = new_name;
 			}
@@ -883,8 +883,8 @@ static void GetTileDesc_Town(TileIndex tile, TileDesc *td)
 		td->str = STR_LAI_TOWN_INDUSTRY_DESCRIPTION_UNDER_CONSTRUCTION;
 	}
 
-	if (hs->grf_prop.grffile != nullptr) {
-		const GRFConfig *gc = GetGRFConfig(hs->grf_prop.grffile->grfid);
+	if (hs->grf_prop.HasGrfFile()) {
+		const GRFConfig *gc = GetGRFConfig(hs->grf_prop.grfid);
 		td->grf = gc->GetName();
 	}
 
diff --git a/src/town_gui.cpp b/src/town_gui.cpp
index 513ec66734..9e7cb11a07 100644
--- a/src/town_gui.cpp
+++ b/src/town_gui.cpp
@@ -1531,8 +1531,8 @@ public:
 	PickerItem GetPickerItem(int cls_id, int id) const override
 	{
 		const auto *spec = HouseSpec::Get(id);
-		if (spec->grf_prop.grffile == nullptr) return {0, spec->Index(), cls_id, id};
-		return {spec->grf_prop.grffile->grfid, spec->grf_prop.local_id, cls_id, id};
+		if (!spec->grf_prop.HasGrfFile()) return {0, spec->Index(), cls_id, id};
+		return {spec->grf_prop.grfid, spec->grf_prop.local_id, cls_id, id};
 	}
 
 	int GetSelectedType() const override { return sel_type; }
@@ -1587,7 +1587,7 @@ public:
 				dst.insert(item);
 			} else {
 				/* Search for spec by grfid and local index. */
-				auto it = std::ranges::find_if(specs, [&item](const HouseSpec &spec) { return spec.grf_prop.grffile != nullptr && spec.grf_prop.grffile->grfid == item.grfid && spec.grf_prop.local_id == item.local_id; });
+				auto it = std::ranges::find_if(specs, [&item](const HouseSpec &spec) { return spec.grf_prop.grfid == item.grfid && spec.grf_prop.local_id == item.local_id; });
 				if (it == specs.end()) {
 					/* Not preset, hide from UI. */
 					dst.insert({item.grfid, item.local_id, -1, -1});
diff --git a/src/vehicle.cpp b/src/vehicle.cpp
index 7e5e63bc30..cff919b975 100644
--- a/src/vehicle.cpp
+++ b/src/vehicle.cpp
@@ -347,7 +347,7 @@ void VehicleLengthChanged(const Vehicle *u)
 {
 	/* show a warning once for each engine in whole game and once for each GRF after each game load */
 	const Engine *engine = u->GetEngine();
-	uint32_t grfid = engine->grf_prop.grffile->grfid;
+	uint32_t grfid = engine->grf_prop.grfid;
 	GRFConfig *grfconfig = GetGRFConfig(grfid);
 	if (_gamelog.GRFBugReverse(grfid, engine->grf_prop.local_id) || !HasBit(grfconfig->grf_bugs, GBUG_VEH_LENGTH)) {
 		ShowNewGrfVehicleError(u->engine_type, STR_NEWGRF_BROKEN, STR_NEWGRF_BROKEN_VEHICLE_LENGTH, GBUG_VEH_LENGTH, true);