Business Contract Obligation Monitoring through use of Multi Tier Contract Ontology

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1 Business Contract Obligation Monitoring through use of Multi Tier Contract Ontology Vandana Kabilan Paul Johannesson Dickson M Rugaimukamu Department Of Computer and System Sciences Royal Institute of Technology and Stockholm University, SE , Sweden E Mail: {vandana, pajo, si-dmr}@dsv.su.se Abstract A core business enterprise function is trading with other business organizations. Such trade relationships are governed by legal contracts. The obligations and fulfillment conditions as stipulated in a business contract demand performance of business activities in the pre-defined choreography. Non-performance could lead to serious legal and/or financial implications. Therefore, it is essential to have integrated business and contract workflow management. Domain knowledge of legal business contracts can be represented using the proposed multi-tier contract ontology. This paper analyzes and models the different obligation types found in a contract and also identifies obligation states through which each obligation passes through. Thereafter, the paper proposes a methodology to monitor contractual obligation through the use of Multi tier Contract Ontology and related contract fulfillment process modeled as Contract Workflow Model. 1. Introduction Legal business contracts are established to agree upon the rules and regulations to govern the business transactions in between the agreement partners. A contract also stipulates and testifies to the legal binding nature of the agreement, as well as the remedial options and rights granted to the partners in case of any disagreement or dispute. Information contained in a contract needs to be assimilated as knowledge, which can be analyzed and reused in the business process management efficiently. We find various research approaches related to e-commerce or business process modeling or contracting. Most contract management tools available today view the contract as a document [35], some as a work flow process [1], while others have represented the contract terms in deontic logic [2] or other AI methodologies [3,4]. Legal dictionaries are also being developed [36]. But any proposed methodology should take in to account the implications of all the domains, which influence a contract, namely: Business Domain Legal, Regulatory Domain

2 Technological and Information Systems Domain. A successful contract is negotiated such that the terms are beneficial to all the parties involved. Thus, a business entity should aim to execute the contract relationship in an optimized flow so as to gain the maximum efficiency and performance compliance and in turn maximum profit. The contract stipulates both implied and explicit obligations, which are legally binding, and need to be fulfilled by the execution of performance as agreed. Therefore, a contract once negotiated and signed cannot be forgotten. It needs to govern and monitor the actual execution of the business processes. Similarly, existing business or workflow models influence the negotiation and acceptance of the contract terms and obligations. A business entity should not accept such terms and conditions, which he is unable to comply or fulfill. Existing methodologies fail to bridge the chasm in between the two domains. Contract compliance and optimum business process management can be achieved if the existing gap between the two areas is bridged. Contract obligation monitoring and tracking is one of the crucial issues to be resolved in this context. This paper proposes a methodology to monitor and track the contract with respect to the business process execution. In order to do so, the paper makes use of the Multi-Tier Contract Ontology [45]. The paper focuses mainly on the analysis of different types of obligations, stipulated in a contract and the various states through which each obligation passes through. Based on the multi tier contract ontology conceptual models, specifically focusing on the obligations and their related fulfilling performances, a Contract Workflow Model (CWM) is deduced. The rest of this paper is organized as follows: In Section 2, we present works of other researchers related to our field of interest and have influenced our research methodologies. Next, we present an overview of the entire Multi-Tier Contract ontology in Section 3. In Section 4 we focus on conceptual models for the Upper Core Layer of the Multi-Tier Contract Ontology followed by a detailed analysis of contract obligation types and obligation states in Section 5. Detailed conceptual models for the domain and template layers maybe referred to in [48]. In Section 6, the use of Contract Workflow Model for obligation monitoring is illustrated. Detailed discussion on the methodology for Contract Workflow Model deduction is out of the scope of this current paper. Finally, the paper concludes with a discussion on other possible applications and potential impact of Contract Knowledge and future work (Section 7). 2. Related Research This research is guided by the ontology design concepts and guidelines as suggested by T. Gruber [5], who proposes clarity, coherence, extensibility, minimal coding bias and ontological commitment as fundamental objectives for any ontology. This paper also adopts the philosophy of Noy and McGuinness [6] that an ontology defines a common vocabulary for researchers who need to share information in a domain. It includes machine-interpretable definitions of basic concepts in the domain and relations among them. This work has been inspired by similar works on ontology of Guarino [7],

3 who has worked on formalizing ontological principles to knowledge engineering methodologies. The use of UML as an ontology-modeling tool has been discussed by some researchers, including Cranefield [46], Gerd Wagner [47]. Increasing use of ontological engineering in the realm of business process engineering has been supported by Deborah McGuinness [8] who identifies the goals for ontological development and proposes guidelines for a centralized knowledge base to capture semantics from domain, standard terms and vocabularies. Howard Smith states [9], Agent based system rely upon ontologies to provide a map or blue print of the space each agent navigates through communication and interoperation with other agents and he also emphasizes on the need for software engineering, business process re engineering and ontological engineering integration. Different E-Contracting approaches such as event driven action semantics [10], component based view as in COSMOS [11] or as Meta schema for workflow [1] exist. Though the workflow aspect has been the focus in [1], the analysis of the contract has been done from a document centric perspective. Daskalopulu, in [12,13] analyses and represents obligation and business exchange transition states through deontic logic. An e-market controller as suggested in [12] implies strict adherence and compliance to the contract specifications. Milosevic [14] proposes the use of Subjective Logic for a Discretionary Enforcement Moderator agent for automated dispute resolution after contract violations. Milosevic has also expressed contractual obligations using genetic software engineering behavior trees in [15]. He uses deontic logic to translate the behavior trees to business process flows. Our approach is based on similar premises as of Milosevic, however, our approach is an integral perspective of contract knowledge and business process workflows. Moreover our representation using conceptual models and workflow patterns to model the contract workflow is easily comprehensible, coherent, and extensible. W.M.P. van der Aalst [16] has proposed several workflow patterns for modeling business workflow, as have also E Sivaraman and M Kamath [17]. Ronald Lee, one of the pioneers of e contracting, has used Petri nets to model documentary credits procedures in [33]. Most of the above work pertains to the realm of e contracting. Some focus of electronic contract negotiation and signing, some on electronic monitoring and enforcement agents, others on technical communication standards like the ebxml initiative, EDI etc. Given the nature of contractual obligations and their executions, a rigid automated monitoring as proposed by Milosevic or Daskalopulu is not practical. As most business strategy and decision making is still carried out by human counterparts, it becomes crucial for the decision makers to have a clear understanding of the contractual obligations and possible repercussions in case of contract violations. Thus, this paper proposes a methodology for semi automated monitoring of contracts based on fostering a clear, comprehensible understanding of contractual obligations, and the performance required to fulfill them. In this regard, the methodology is applicable to contracts established electronically or traditionally across the table.

4 3. Multi Tier Contract Ontology Contracts can be of diverse types [25]. The domain and scope of each type varies largely. Thus a single contract ontology layer would be too large as well as diverse in nature to be of any practical use. In order to capture the entire range of business related contracts in a single framework; we propose a layered, multi tier contract ontology, which moves from the abstract to the specific Meta data definition progressively down the stratifications. Currently, we have identified a minimum of three different layers as presented below. Other extensions and layers may be possible. The Upper Core Layer represents a general composition of a contract, which may be applicable across most of the prevalent types of contracts. The concepts defined here may be considered to be the atomic blocks based on which all other contract types may be defined. Fundamental concepts like role, consideration, and obligation are defined here, as presented in section 4. The second layer is Specific Domain layer or contract type specific collection of several contract type ontology. Each ontology represents a specific contract type like property lease rental, employment contract, and sale of goods amongst others. Each contract type inherits all fundamental features of the upper layer and thereafter specializes on the specific knowledge particular to that contract domain. The focus of our research has been on business and corporate contract types. Initially, we have concentrated on sale and purchase of goods contract domain. In this context, we have based our conceptual models on the UNCISG [37], UNIDROIT [40] principles for International Commercial Contracts [39] and UNCITRAL [38] model law and recommendations. We have also mapped to other existing ontologies like product catalogues (UNSPSC [22], CPV [23]), payment terms (standard payment methods), and delivery terms (ex INCOTERMS [41), which can be applicable across diverse contract types. Each contract type is an extension or restriction of the upper layer contract ontology to a specified domain. The obligations, rights and their implications have been analyzed based on Jan Ramberg s book on International Commercial Transactions [24]. The third layer, Template Layer, consists of a collection of template like definitions for established or recommended contract models like the International Chamber of Commerce s [18] contract model for International Sale of Goods [19], European Union s SIMAP [20] online procurement contract models etc. The template layer is visualized as a detailed definition of a particular contract type and could be a recommended contract form based on a contract type as modeled in the shared domain layer. The template layer may bind the conceptual components to specific range of values, thereby limiting their re-usability outside their domain of application.

5 The Multi Tier Contract Ontology models explicit, declarative and strategic knowledge contained within a contract. Interdependencies and relationships between the components of a contract are represented. The three-tier contract ontology is a stratified presentation of information, moving from the most generic global contract ontology domain to the shared contract ontology domain and further down to implementation specific template contract ontology. The procedural knowledge and strategic knowledge as presented through the choreography of obligations and performance events in the contract, is then modeled as a set of Contract Workflow Models (CWM)(Section 6). The actual business workflow should be as close and similar to the deduced CWM to be compliant with the contract conditions. 4. Upper Core Layer Contract Ontology Figure 1: Outline for Upper Level Contract Ontology Figure 1 is an extract from the current working model for the global upper layer. We illustrate the concepts through the following business case scenario. Assuming a hypothetical case scenario (Figure 2) where a seller promises to sell cars to another person (buyer) in return for some amount of money. A promise is a

6 statement of commitment to fulfill some act or perform certain deeds. When a promise is made with the legal intent to back it up in any court, it becomes a legal obligation or commitment. Seller Delivers Car Car $ $ $ Contract governs transaction Seller Promises Buyer of Car Contract for Buy Sell of Car Seller Of Car Buyer Pays for Car Figure 2: Business Case Scenario Example Cars are the object or consideration of the Promise. Legally, a consideration is any material or abstract benefit or thing of value for the exchange of which two parties agree to enter in to a contract. It could also be simply a promise to fix a leaky roof or a promise not to do something [21,28]. Selling becomes the performance, which fulfills the above promise. The promise to sell is an obligation; which is realized only when the actual business act of giving the cars in return for the money is performed. An obligation must have a Receiver or an Acknowledger or a Claimant or a Beneficiary of the obligation, that is one who receives the consideration or is the recipient for whom the promised act is being performed or carried out. The Buyer who buys the cars and pays money for it is the Receiver of the obligation to sell. Contracts are legal testament to the promises (Obligations/commitments) made by the two parties to each other and spell out the details constituting the obligations, the accepted boundaries and performance criteria like time, venue etc. The two parties promise to carry out certain acts in order to fulfill their commitments, this presumption can be held valid if and only if the two parties have the necessary capability or competence or ability to perform the said deeds. That is the seller promising to sell the car must own the car and the buyer must have the money to pay for it. Lastly the contract must outline the terms and conditions under which the promised performance shall occur. In a normal situation, a contract is executed as planned and agreed. In case the expected performance does not occur within the expected time frame or occurs in an unsatisfactory manner or is delayed due to forces beyond the control of the promisor, then the primary obligation goes in to a state of un-fulfillment. The occurrence of the Non Performance event activates certain pre-agreed rights on behalf of the promisee. In this case, the buyer may have the

7 right to seek remedy in the form of some interest or penalty, or may choose to terminate in accordance with the agreement. But the buyer may also choose not to do anything and could settle the issue by mutual agreement. However, whatever course of action the buyer chooses, the seller (the promisor of the primary obligation) is bound to a reconciliatory promise to fulfill the remedy asked. This secondary or reconciliatory promise may also include the fulfillment of the initial primary promise to sell. The above was a very simple case scenario where we see that obligations have different natures; obligations may give rise to other obligations and rights. Rights too may give rise to new obligations being formed etc. In the following section, we present the obligation type and obligation state model extracts from the Upper Core Level Contract ontology. 5. Obligation Types and Obligation States Figure 3: Common Obligation Types As proposed by others like Ronald Lee [33], Yao-Hua Tan [10] and Daskalopulu [3,4], we acknowledge that the statements in a legal contract are informative, declarative or performative. Informative statements pertain to the description of the actors, the subject of the contract, jurisdiction and other pertinent information. Declarative or performative statements are statements of intentions or conditions, which change states through the performance of specified conditions. They are usually of the following types: 1. Obligations: Obligations are mandatory. They have an obligation owner, who is the recipient of the obligation and there is an obligation ownee, who is the one who has to carry out the obligation. It is mandatory for the ownee to execute the obligation condition once and only once in every single execution of the contract.

8 2. Permissions/Rights: Permissions or Rights too have a rights Owner and a ownee, but the right is executed by the owner in this case. The execution of a right is of an optional nature or it may be conditional depending on the execution of some other obligation. 3. Prohibitions: Prohibitions are statements of whatever actions should not be executed or whatever actions may be unacceptable to either or both parties. Obligations are bound to their performative actions or non-performative actions for their fulfillment. Based on the nature of their fulfillment execution, we propose a categorization of obligations in to the following abstract categories, for ease of grouping and understanding, refer Figure 3 above: 1. Primary obligation: has to be fulfilled whenever the contract is to be executed and is the principal objective behind the agreement itself. Like the obligation of a seller to deliver goods in conformity to the contract or that of a buyer to accept and pay for goods as ordered. 2. Reciprocal obligation: could be a primary obligation in itself, but is also the obligation expected to be fulfilled by the counter party in response to the execution of the primary obligation. E.g. the buyer s obligation to pay is reciprocal to the seller s obligation to deliver and vice versa. Also the buyer s obligation to pay is a primary obligation for the buyer. 3. Conditional obligation: does not need to be activated under the normal course of events. Most remedial rights and obligations come in this category, like the buyer s right to seek compensation for failed delivery, binds the seller to deliver the goods at his added cost etc. 4. Secondary obligation: gets activated as a part of some other obligation. Like the sellers obligation to package goods suitable for transportation could be said to be sub unit of his primary obligation to deliver. Also based on the contextual nature of the obligation, which require the specific type of performance, business, legal or ethical as the case maybe, obligations can also be grouped as: Legal Obligation :In a legal business contract all statements are legally binding and have legal implications. However, we propose the category of legal obligation to differentiate those obligations that require some specific legal actions to be carried out to fulfill them. The legal acts may or may not be part of the business management process Business Obligation: Similarly, business obligations are also legally binding. But we propose this term to categorise all those obligations, which are specifically related to business performance. Business obligations are further typified as monetary obligation and non-monetary obligation. Monetary obligations are those that deal with some economic transactions or exchange. We summarize that all business obligations need not necessarily be economic commitments. Commitments like the buyer has to send the order once he has

9 contracted to purchase goods or that the buyer has the obligation to arrange for carrier and inform the seller etc require business execution but do not have economic implications in between the buyer and the seller. We term these types of obligations as non-monetary obligations. Moral/Ethical Obligation: Yet another category is moral or ethical obligations. These may not be severely binding but are more practically or socially expected obligations. Like for example, though it maybe the obligation of the buyer to pick up the goods from the seller s premises, he may request the seller to help in arranging the transportation or require some other help in arranging the official customs duty etc. The seller, though he may not be legally bound to assist the buyer, he is morally bound to aid the buyer subject to the buyer requesting such help. Figure 4: Obligation State Models Individual obligations may belong to more than one category simultaneously. In order to track the contract fulfillment process more systematically, we have identified some stages in the contract execution phases wherein each contract obligation may be said to go through certain Obligation States. The proposed obligation states are similar to most common business activity states and are also adapted from similar obligation state definitions proposed by Lee [33], Yao-Hua Tan [10] (Figure 4).

10 Figure 5: State Transformation Diagram of Obligation Figure 5 illustrates an example of obligation state changes in response to the business performance events for a typical obligation to deliver on behalf of the seller. Inactive: Every obligation can be said to be in inactive state once the contract has been signed but contract execution is yet to be started. The obligation will remain in inactive state in between cycles of contract execution also. Active: An obligation may be said to be active when the triggering performance event has been issued. For example, once the buyer sends the Purchase Order to the seller and he receives it, then the seller s obligation to deliver is triggered. Pending: When fulfillment activity from performer s side has been accomplished but the acceptance from the other party is still awaited. When the seller has dispatched the goods from his warehouse, and is waiting for the third party carrier to deliver the goods to the buyer. Alternatively, an obligation may remain in the pending state, till the all the necessary fulfillment criteria are satisfied. The buyer may have received the goods but may have rejected the goods as being unsatisfactory. Fulfilled: when the performance conditions are satisfied within the stipulated performance conditions. Once the buyer inspects the goods and accepts the delivery. Terminated/Cancelled: if the activation of the obligation is terminated or cancelled by the Obligee, mutually, or legal authority. 6. Contract Workflow Model In this section, we discuss one possible application of the proposed contract knowledge base. Multi tier Contract Ontology provides information regarding the obligations and their expected performance activities. From the contract obligation models

11 (Figure 3,4) we get the states through which an obligation can pass through. Combined together, we get procedural knowledge regarding the expected flow of business actions within individual contracting parties business process workflow. This expected choreography of business actions is modeled as a Contract Workflow Model using workflow patterns and notations. SELLER BUYER Legend: T1: Contract signed T2: order received T3: Receive carrier info T4: get material T5: make goods T6:Mark goods T7: carrier arranged T8: Order cancelled T9: Pack goods T10: Ship goods T11: Receive Receipt T12: rejection received T13: Replace goods/pay penalty T14:Send Invoice T15: Receive payment Obligation to deliver state transitions: C1: Obligation Inactive C2:Obl. Active C3: Obl. Cancelled C4: contract execution terminated. C5: Obligation to deliver fulfillment pending. C6: Obligation Fulfilled C7:Obligation unfulfilled,c8: reconciliatory obligation active C9: reconciliatory fulfilled, Right to receive payment invoked C10: Buyer s obligation to pay fulfilled, seller s right to receive pay fulfilled Figure 6: Sample CWM for a seller s obligations in a sale of goods contract. The Contract Workflow Model (CWM) is deduced from the instance data and informative knowledge present in the contract instance and the conceptual models for the same contract type (from Multi tier Contract Ontology). It is the expected workflow pattern, which complies with the agreed upon obligation and fulfillment pattern. The Contract Workflow Model would then be the reference for comparison with existing internal business process or shared workflow models of the business partners. Ideally, the

12 existing business process flow should be identical with the contract workflow pattern or at least within tolerable limits of performance and contract compliance. The Contract Workflow Model is also instrumental in enabling automated or semi-automated tracking of obligation fulfillment. The Contract workflow model identifies individual obligations and the various states they go through in relation to the occurrence of related business or legal events. Thus, the obligation state transition can be tracked and monitored with respect to the actual occurrence of the identified business event in the business process workflow of each individual party. A mapping to business process workflow or existing business management systems can be made based on the identified obligation state transition and business activity interaction point. For the current phase of human-to-human knowledge transfer a guideline for deducing the CWM has been designed. But, a semi-automated deduction logic using Object Constraint Language for UML is the subject of ongoing work. 7. Conclusion In this paper we have identified the existing gap between business process management and business contract execution and fulfillment. The paper has also identified the common obligation types that are present in a business contract and has also proposed an obligation state identification for denoting the stages through which every contract obligation passes. We have also illustrated the use of Multi tier Contract Ontology for deducing the contract workflow model as a means to affect contract and business process integration as well as to monitor the contract fulfillment process. Contracts and Business are established and carried out by human agents at some level or the other. Contracts are testament to agreed intentions of human partners and their actual behavior cannot be predicted. Thus, it is impractical to have rigid automated agents for contract enforcement or for negotiation. However, an easy accessible knowledge pool can provide invaluable aid in the decision-making and process management regarding contractual obligations and their required fulfillment. Semi-automated decision support or obligation tracking agent tools are within the scope of our ongoing research work. The main benefit of having a centralized contract knowledge base is that a business organization may effectively increase profitability by reusing knowledge gained from legal domain, from their previous experience. Future work in this field includes analysis and modeling of other types of business and legal contracts. Migration to human to machine, machine to human methodologies are possible extensions to ongoing work. 8. References 1. Kamalakar Karlapalem, Ajay R Dani and PP. Radha Krishna; A frame Work for Modeling Electronic Contracts; ER 2001, LNCS 2224 pp Yao-Hua Tan, Walter Thoen. Using Event Semantics for Modeling Contracts. Proceedings of 35th Hawaii International Conference on System Sciences 2002.

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