15. A computer-readable storage media having instructions stored thereon that when executed by a computing device cause the computing device to perform acts, comprising: populating a data structure with document tokens selected from signatures of documents and member tokens selected from database members, the data structure including entries identifying co-occurrences of the document tokens and the member tokens; identifying individual documents that cannot match individual database members using the co-occurrences identified in the data structure; receiving a remainder of the documents; and verifying whether sub-strings of the remainder of the documents match the individual database members.
15. A computer-readable storage media having instructions stored thereon that when executed by a computing device cause the computing device to perform acts, comprising: populating a data structure with document tokens selected from signatures of documents and member tokens selected from database members, the data structure including entries identifying co-occurrences of the document tokens and the member tokens; identifying individual documents that cannot match individual database members using the co-occurrences identified in the data structure; receiving a remainder of the documents; and verifying whether sub-strings of the remainder of the documents match the individual database members. 16. The computer-readable storage media of claim 15 , wherein the data structure comprises a summary structure, the acts further comprising pre-populating the summary structure with token-signature pairs of the database members and wherein relatively less definitive member tokens are eliminated to decrease an overall size of the summary structure.