Additive Manufacturing (AM) is a set of technologies that has historically found fertile applications in the aerospace and healthcare industries, while adoption in the Oil and Gas (O&G) sector has progressed slower. Nonetheless, AM is reaching maturity in this industry as well, allowing for significant innovation. The scope of this paper is to describe how AM is integrated within the value chain of a major O&G service company, highlighting specific peculiarities for each of its business segments. "Fullstream" activities cover the whole O&G value chain, from the exploration of reservoirs and production (upstream) to the transportation and storage of hydrocarbons (midstream), as well as refining and industrial power processing (downstream). AM technologies within the O&G service provider have originally been deployed for rapid prototyping and have matured as strategic manufacturing pillars. Several manufacturing methods within the AM landscape can be deployed, depending on the technical requirements of the components and the environment in which they are operating. Here, powder bed processes are in focus, with an emphasis on the Selective Laser Melting (SLM) process. O&G equipment end users face several challenges when dealing with spare parts management, such as performance, total cost of ownership, procurement time, inventory levels, and obsolescence. From an OEM standpoint, serving a wide fleet with a variety of products and their different versions (with an unpredictable and unstable demand) is challenging. AM is the tool that enables a new way to serve such an installed fleet. The O&G service provider has already experimented several applications regarding obsolete spare parts reintroduction through AM, gaining strong benefits (50%+) in terms of cost and procurement time reduction. Thus, it is important to continue adopting AM to deliver faster outcomes for the customer. This, in turn, fosters the development of sound know-how and references, which can then be used to develop further solutions and value propositions for the customers.