LOD-Enabled Public Contract Matchmaking
Public Contracts Filing Application
Seeking the best possible match is an activity repeatedly undertaken by both sides of the procurement market: buyers (contracting authorities) and suppliers (bidders). Since most of the underlying computation, and even a considerable part of the GUI components, are similar for both cases, it makes sense to provide a single, web-based interface for them, which can be characterized as a contentmanagement system for public contracts (and associated tenders). We denote the prototype developed simply as Public Contract Filing Application (PCFA). Its features are (partly dynamically) derived from the Public Contracts Ontology.
Buyer's and Supplier's View
The buyers can use PCFA to create and manage their calls for tenders, publish them when they are ready, and wait for tenders from the candidate suppliers, as seen in Fig. 3. PCFA allows the buyer to compare the proposed call for tenders with other public contracts (published by the same buyer or by others) using the matchmaking functionality. The buyers can thus take into account, e.g., the cost or duration of similar contracts in the past, and adjust the proposed price or time schedule accordingly.
PCFA can help the buyers even further by allowing them to ﬁnd suitable suppliers for their proposed call for tenders, as seen in Fig. 4. They can thus explicitly invite such potential suppliers via email and thus increase the competition for the given call. A published call for tenders can also be withdrawn; if the buyer later publishes a withdrawn call again, it is published as a new call, which ensures that the whole history of the procurement process is recorded properly. When the deadline for tenders passes, the buyers can easily reject the tenders that do not meet the criteria of the call, and they can also award the tender that oﬀers the best conditions. Finally, when the public contract has been fulﬁlled, the buyer can brieﬂy evaluate the progress and the outcome of the contract and record it in the application. This typically amounts to providing the actual price of the contract (which may be signiﬁcantly higher than the price proposed in the awarded tender), the actual date when the contract was ﬁnished, and the
Fig. 3. Open calls for tenders from a buyer's perspective
overall experience of the buyer with this particular supplier. This information can later help the same buyer or other buyers in the future.
The interested suppliers can see the open calls for tenders suitable for them. This functionality is again provided by the matchmaking module. As mentioned above, a potential supplier can also be invited, by a contracting authority, to submit a tender to a certain call. The supplier can see and manage the received invitations in the PCFA as well. The invitations can be rejected or accepted; the latter automatically creates a tender. Alternatively, suppliers can ﬁnd an open call for tenders on their own, and create a tender for it. The tender can be edited by the supplier and, when ready, submitted to the contracting authority. The suppliers are always informed by email when some update takes place for the call for tenders for which they submitted a tender.
Fig. 4. Suitable suppliers for a call for tenders
-  The code of the PCFA is maintained at https://github.com/opendatacz/ pc-ﬁling-app