The feasibility study on an Open Ticketing Interface (oTick) investigates how public transport operators can open their ticket sales to third‑party providers and thereby attract new customer segments. The study combines a quantitative online survey of 39 transport operators with 10 fully completed responses and a qualitative set of expert interviews. The operators represent 12 German federal states and cover a wide spectrum of sizes, from a small company moving 5 million passengers per year to a large one transporting 285 million passengers annually. On average, the participating operators move 82 million passengers each year. The survey revealed that transport associations are primarily responsible for tariff design, financing new digital sales projects, and developing digital sales strategies, while only a minority manage central billing, sales, and payment systems.
The qualitative interviews, conducted with experts from DELTA, DELFI, HUSST4MAAS and other industry stakeholders, explored issues such as standardisation, data protection, and the practical requirements of a unified interface. The interviews were structured according to Mayring’s content analysis and were carried out both in person and via video conference. Participants highlighted the need for a common technical standard that would allow seamless integration of ticketing services into existing booking and payment workflows.
Based on the survey and interview findings, the study proposes a universal technical interface for third‑party ticket sales. The interface is defined as an OpenAPI 3.0.1 specification (oTick API V2) hosted at https://api-alpha.themobilitybox.com/v2. The API introduces four core concepts: Area (geographical validity of a ticket), Product (ticket definition including price and area), Coupon (ordered product ready for redemption), and Ticket (the final valid travel pass). The specification includes schemas for order creation responses, coupons, and products, and demonstrates how an order can be placed and a ticket generated through a simple RESTful call. This design aims to lower technical barriers for partners such as airlines, hotels, and event organisers, enabling them to offer public transport tickets alongside their own services.
The study also outlines a commercial model that balances revenue sharing between operators and third‑party sellers, ensuring that operators retain control over pricing and data while benefiting from increased distribution reach. A discussion section evaluates the potential impact of the interface on passenger numbers, noting that the current “tariff jungle” of over 200 fare structures in Germany hampers casual use of public transport. By simplifying access through a single API, the project expects to reduce friction for occasional users and support the sector’s goal of doubling ridership by 2030.
Collaboration was central to the project. Sheldonconsult GmbH coordinated the study design and partner networking, while the House of Logistics and Mobility (HOLM) GmbH facilitated the creation of a platform to disseminate the findings. Stadtwerke Halle GmbH, the parent company of HAVAG, provided industry expertise and direct access to operators. The study was conducted within a broader funding framework, with the grant (Zuwendung) earmarked for research and development of open mobility solutions. The project’s outcomes are intended to inform policy makers, operators, and third‑party developers, fostering a more integrated and customer‑friendly public transport ecosystem.