Regular expressions used for searching for patterns in captured objects can be grouped into attributes. Such attributes can be associated with captured objects using tags stored in a database. In one embodiment, the present invention includes capturing an object being transmitted over a network, and determining that a regular expression appears in the object, the regular expression belonging to a group of one or more regular expressions associated with an attribute. If a regular expression associated with the attribute is found in the object, then an attribute field of a tag containing metadata related to the captured object is set to indicate the presence of the attribute in the captured object. The presence of the attribute in the captured object can now be determined from the tag, which can be stored in a database.