Method for automatic and dynamic determination of main domains belonging to an entity, comprising the following steps performed by a computer system: - a searching step, wherein a search list is generated by using a target name as input to a at least one first data source (3a, 3b), in particular a merge and acquisition data base or a web search engine; - an extraction step, wherein a list of main domains, in particular second-level domains, is extracted from the search list; - a counting step, wherein a first score is determined for each main domain of the list of main domains by counting the number of the appearances within the list of main domains; - a keyword generation step, wherein at least one validation keyword is generated on basis of the target name; - a scoring step, wherein at least one second score is determined for each main domain of the list of main domains by multiplying the number of appearances of the at least one validation keyword within a at least one second data source (3A, 3C, 3D, 3E) with a validation keyword factor assigned to the validation keyword; - a calculation step, wherein a final score is determined for each main domain as sum of the first score and the at least one second score; and - a validation step, in which the validity of each main domain is determined on basis of a comparison of the final score of each main domain with a threshold, wherein the main domain is considered as valid if the final score is above the threshold (step 310), and wherein the main domain is considered as invalid if the final score in equal or below the threshold, wherein a valid main domain is a main domain that is identified as belonging to the organization or entity, whereas an invalid main domain is a main domain that is identified as not belonging to the organization or entity. - a searching step, wherein a search list is generated by using a target name as input to a at least one first data source (3a, 3b), in particular a merge and acquisition data base or a web search engine; - an extraction step, wherein a list of main domains, in particular second-level domains, is extracted from the search list; - a counting step, wherein a first score is determined for each main domain of the list of main domains by counting the number of the appearances within the list of main domains; - a keyword generation step, wherein at least one validation keyword is generated on basis of the target name; - a scoring step, wherein at least one second score is determined for each main domain of the list of main domains by multiplying the number of appearances of the at least one validation keyword within a at least one second data source (3A, 3C, 3D, 3E) with a validation keyword factor assigned to the validation keyword; - a calculation step, wherein a final score is determined for each main domain as sum of the first score and the at least one second score; and - a validation step, in which the validity of each main domain is determined on basis of a comparison of the final score of each main domain with a threshold, wherein the main domain is considered as valid if the final score is above the threshold (step 310), and wherein the main domain is considered as invalid if the final score in equal or below the threshold, wherein a valid main domain is a main domain that is identified as belonging to the organization or entity, whereas an invalid main domain is a main domain that is identified as not belonging to the organization or entity.