## 4 Literature Review  
By investigating the publications more thoroughly, their substantial contribution to the manufacturing landscape is revealed [51]. MaaS' main goal is to automatically pair requests and applicable manufacturing capabilities through algorithms [12]. Current industries do not always fulfill the standards to easily integrate frameworks like MaaS in their operations. To overcome the current challenges, each of the selected publications for this review contributes in either a theoretical or a functional way. Therefore, the papers can be classified into three main categories, based on their content: \"MaaS theoretical approach\", \"MaaS architectures\", and \"Data innovations\". For instance, [PERSON] [52] presents the six enablers which will strengthen universal manufacturing, providing flexibility and affinity. In this context, by establishing modern industrial strategies, such as digitization or open manufacturing, the production needs regardless of type and complexity will be covered, ensuring companies an optimization, free from boundaries concerning the market, natural or human-caused failures, and the environment. Publications that discuss the manufacturing-as-a-service subject from a theoretical and conceptual view are mentioned in Table 2, arranged in specific thematic sections. At the same time, a significant part of the documents researched proposes a specific mechanism to preserve trust [7] and immediacy [9] between the different stakeholders of a manufacturing digital thread, which is formed thanks to the servitization [42; 53] of MaaS. For example, [PERSON], [PERSON], and [PERSON] [10] recommend that final consumers name their own prices, and the mechanism designed by them tracks down service providers willing to assume the production of the part under the declared price. [PERSON] et al. [54] upgrade the concept of customization by providing the ability of parameterized, composed, and optimized products. Publications which suggest a unique, designed mechanism for the unhindered integration of MaaS in the manufacturing sector are listed in Table 3, divided into particularly important categories. Most of the collected papers, however, concentrate on the provision of data management data solutions required for the digitization and democratization [55] MaaS includes. [PERSON] and [PERSON] [2] focus on the advancement of such software architecture, which connects customers with manufacturing-service providers directly, securing data transparency, integrity, origin, and ownership to creators. Documents relevant to data management solutions are listed in Table 4 below and even separated into targeted thematic modules. Theoretical approaches, architectures, and data innovations in MaaS are inherently interconnected, forming a cohesive framework for its development and implementation. Theoretical foundations define key principles and service models, guiding the design of architectures that enable scalable and interoperable MaaS platforms. These architectures, in turn, rely on data innovations to enhance decision-making, optimize resource allocation, and ensure secure transactions. Together, these categories create a dynamic ecosystem where conceptual models inform structural frameworks, which are further refined through data-driven advancements, ensuring efficient and adaptive MaaS solutions. Concerning the methodologies involved in the investigated publications, many of them suggest a technical approach for the integration of MaaS in modern industries. More specifically, an approach may illustrate the structure of a production flow and the data allocation [56] passing stakeholders until the final customer and are designed with the assistance of computer-aided programs [57]. Other mechanisms recommend a decision management system [43], which utilizes available data to simplify the procedures of MaaS in organizations. Through the simulation of a marketplace, [PERSON], [PERSON], and [PERSON] [9] evaluate the impact of various variables, such as pricing.