diff --git a/src/company_base.h b/src/company_base.h
new file mode 100644
--- /dev/null
+++ b/src/company_base.h
@@ -0,0 +1,107 @@
+/* $Id$ */
+
+/** @file company_base.h Definition of stuff that is very close to a company, like the company struct itself. */
+
+#ifndef COMPANY_BASE_H
+#define COMPANY_BASE_H
+
+#include "company_type.h"
+#include "oldpool.h"
+#include "road_type.h"
+#include "rail_type.h"
+#include "date_type.h"
+#include "engine_type.h"
+#include "livery.h"
+#include "autoreplace_type.h"
+#include "economy_type.h"
+#include "tile_type.h"
+
+struct CompanyEconomyEntry {
+	Money income;
+	Money expenses;
+	int32 delivered_cargo;
+	int32 performance_history; ///< company score (scale 0-1000)
+	Money company_value;
+};
+
+/* The third parameter and the number after >> MUST be the same,
+ * otherwise more (or less) companies will be allowed to be
+ * created than what MAX_COMPANIES specifies!
+ */
+DECLARE_OLD_POOL(Company, Company, 1, MAX_COMPANIES >> 1)
+
+struct Company : PoolItem<Company, CompanyByte, &_Company_pool> {
+	Company(uint16 name_1 = 0, bool is_ai = false);
+	~Company();
+
+	uint32 name_2;
+	uint16 name_1;
+	char *name;
+
+	uint16 president_name_1;
+	uint32 president_name_2;
+	char *president_name;
+
+	CompanyManagerFace face;
+
+	Money money;
+	byte money_fraction;
+	Money current_loan;
+
+	byte colour;
+	Livery livery[LS_END];
+	RailTypes avail_railtypes;
+	RoadTypes avail_roadtypes;
+	byte block_preview;
+
+	uint32 cargo_types; ///< which cargo types were transported the last year
+
+	TileIndex location_of_HQ;
+	TileIndex last_build_coordinate;
+
+	OwnerByte share_owners[4];
+
+	Year inaugurated_year;
+	byte num_valid_stat_ent;
+
+	byte quarters_of_bankrupcy;
+	byte bankrupt_asked; ///< which companies were asked about buying it?
+	int16 bankrupt_timeout;
+	Money bankrupt_value;
+
+	bool is_ai;
+
+	Money yearly_expenses[3][EXPENSES_END];
+	CompanyEconomyEntry cur_economy;
+	CompanyEconomyEntry old_economy[24];
+	EngineRenewList engine_renew_list; ///< Defined later
+	bool engine_renew;
+	bool renew_keep_length;
+	int16 engine_renew_months;
+	uint32 engine_renew_money;
+	uint16 *num_engines; ///< caches the number of engines of each type the company owns (no need to save this)
+
+	inline bool IsValid() const { return this->name_1 != 0; }
+};
+
+static inline bool IsValidCompanyID(CompanyID company)
+{
+	return (uint)company < GetCompanyPoolSize() && GetCompany(company)->IsValid();
+}
+
+#define FOR_ALL_COMPANIES_FROM(d, start) for (d = GetCompany(start); d != NULL; d = (d->index + 1U < GetCompanyPoolSize()) ? GetCompany(d->index + 1U) : NULL) if (d->IsValid())
+#define FOR_ALL_COMPANIES(d) FOR_ALL_COMPANIES_FROM(d, 0)
+
+static inline byte ActiveCompanyCount()
+{
+	const Company *c;
+	byte count = 0;
+
+	FOR_ALL_COMPANIES(c) count++;
+
+	return count;
+}
+
+Money CalculateCompanyValue(const Company *c);
+
+#endif /* COMPANY_BASE_H */