In order to achieve a high level of cyber security awareness most mid to large sized companies use Security Information and Event Management (SIEM) embedded into a Security Operations Center. These systems enable the centralized collection and analysis of security relevant information generated by a variety of different systems, to detect advanced threats and to improve reaction time in case of an incident. In this paper, we derive a generic SIEM pattern by analyzing already existing tools on the market, among additional information. Thereby, we adhere to a bottom-up process for pattern identification and authoring. This article can serve as a foundation to understand SIEM in general and support developers of existing or new SIEM systems to increase reusability by defining and identifying general software modules inherent in SIEM.