diff --git a/libraries/chain/include/graphene/chain/line_of_credit.hpp b/libraries/chain/include/graphene/chain/line_of_credit.hpp
new file mode 100644
index 00000000..d75a4318
--- /dev/null
+++ b/libraries/chain/include/graphene/chain/line_of_credit.hpp
@@ -0,0 +1,146 @@
+#pragma once
+
+namespace graphene { namespace chain {
+
+   struct line_of_credit
+   {
+      enum flag
+      {
+         /** 
+          * Debt may be increased via credit_passthrough operation, controlled by borrower
+          **/
+         bool              allow_lender_passthrough  = 0x01,
+         bool              allow_borrower_passthrough  = 0x02,
+         /** borrower may pull BitUSD from lender */
+         bool              allow_cash_advance      = 0x04,
+         /** the lender may change the interest rate */
+         bool              allow_variable_interest = 0x08
+      };
+
+      account_id_type   borrower;
+      account_id_type   lender;
+      share_type        debt;
+      share_type        credit_limit;
+      share_type        passthrough_fee;
+      asset_id_type     asset_type;
+      /** accumulated daily, compounded every update */
+      uint16_t          interest_apr = 0;
+      uint8_t           flags = 0;
+      /** requires borrower and lender to approve update */
+      digest_type       loan_contract_digest;
+   };
+
+   /**
+    *  Index on borrower/asset_type and lender/asset_type
+    */
+   class line_of_credit_object : public db::abstract_object<line_of_credit_object>
+   {
+      static const uint8_t space_id = protocol_ids;
+      static const uint8_t type_id  = line_of_credit_object_type;
+
+      account_id_type borrower()const { return terms.borrower;                                }
+      account_id_type lender()const   { return terms.lender;                                  }
+      asset debt()const               { return asset( terms.debt, terms.asset_type );         }
+      asset credit_limit()const       { return asset( terms.credit_limit, terms.asset_type ); }
+      asset_id_type asset_type()const { return term.asset_type; }
+
+      line_of_credit terms;
+      time_point_sec last_update;
+
+      /**
+       *  Both borrower and lender must approve of the line of credit before any
+       *  debts may accrue. 
+       */
+      bool   borrower_approved = false;
+      bool   borrower_lender_approved = false;
+   };
+
+   struct by_borrower;
+   struct by_lender;
+
+   /**
+    * @ingroup object_index
+    */
+   typedef multi_index_container<
+      line_of_credit_object,
+      indexed_by<
+         ordered_unique< tag<by_id>, member< object, object_id_type, &object::id > >,
+         ordered_non_unique< tag<by_borrower>, composite_key<
+            line_of_credit_object,
+            const_member_fun<line_of_credit_object, account_id_type, &line_of_credit_object::borrower>,
+            const_member_fun<line_of_credit_object, asset_id_type, &line_of_credit_object::asset_type> >
+         >,
+         ordered_non_unique< tag<by_lender>, composite_key<
+            line_of_credit_object,
+            const_member_fun<line_of_credit_object, account_id_type, &line_of_credit_object::lender>,
+            const_member_fun<line_of_credit_object, asset_id_type, &line_of_credit_object::asset_type> >
+         >
+      >
+   > line_of_credit_object_multi_index_type;
+   typedef generic_index<line_of_credit_object, line_of_credit_object_multi_index_type> line_of_credit_index;
+
+   struct line_of_credit_create_operation
+   {
+      asset            fee;
+      account_id_type  creator; ///< pays the transaction fee and approves terms by default
+      line_of_credit   terms;
+   };
+
+   struct line_of_credit_accept_terms_operation
+   {
+      asset                    fee;
+      line_of_credit_id_type   id;
+      account_id_type          acceptor;
+   };
+
+   struct line_of_credit_update_operation
+   {
+      asset                    fee;  ///< paid for by terms.lender
+      account_id_type          updater; ///< account performing the update
+      line_of_credit_id_type   id;
+      /**
+       * Lender may increase or lower, borrower may increase
+       */
+      uint16_t                 new_interest_rate = 0;
+      uint8_t                  flags;
+      /**
+       * Lender may increase or lower, borrower may lower
+       */
+      asset                    new_credit_limit;
+   };
+
+   /**
+    *  This operation is used to transfer the debt to a debt
+    *  collector.
+    */
+   struct line_of_credit_transfer_debt_operation
+   {
+      asset                    fee; ///< paid for by current_lender
+      line_of_credit_id_type   loc;
+      account_id_type          current_lender;
+      account_id_type          new_lender;
+   };
+
+
+   /**
+    * @brief enables payment of 3rd parties by rebalancing debts among users
+    */
+   struct line_of_credit_passthrough_operation
+   {
+      struct transfer_node
+      {
+         line_of_credit_id_type loc;
+         account_id_type        borrower;
+         account_id_type        lender;
+         share_type             delta_debt;
+         share_type             fee_paid; ///< always paid to the lender
+      };
+
+      asset                  fee;
+      account_id_type        fee_payer; ///< accout with actual asset to pay fee
+      account_id_type        from; ///< account funding the init_amount
+      asset                  init_amount;
+      vector<transfer_node>  passthrough; ///< pass through nodes
+   };
+
+} } // graphene / chain