A method, computer program and system for optimizing similarity string filtering are disclosed. A first data string comprising one or more data characters and selecting a second data string comprising one or more data characters are selected. At least one of a defined set of shapes is applied to the first data string to generate one or more patterns associated with the first data string. At least one of the defined set of shapes is applied to the second data string to generate one or more patterns associated with the second data string. The one or more patterns associated with the first data string are compared with the one or more patterns associated with the second data string to determine if one or more matching patterns exist. The first data string and the second data string are linked if one or more matching patterns exist.