Information extraction and annotation systems and methods for use in annotating and determining annotation instances are provided herein. Exemplary methods include receiving training documents having annotated words, identifying a predetermined number of characters preceding and following each annotated word for each of the training documents to determine a context for each of the annotated words, performing an alignment of an annotated word and its context with characters in the target document, identifying common sequences, and assigning annotations to words in the target document when common sequences are found.