The paper discusses shallow semantic annotation of Bulgarian treebank. Our goal is to construct the next layer of linguistic interpretation over the morphological and syntactic layers that have already been encoded in the treebank. The annotation is called shallow because it encodes only the senses for the non-functional words and the relations between the semantic indices connected to them. We do not encode quantifiers and scope information. An ontology is employed as a stock of the concepts and relations that form the word senses. Our lexicon is based on the Generative Lexicon (GL) model (Pustejovsky 1995) as it was implemented in the SIMPLE project (Lenci et. al. 2000). GL defines the way in which the words are connected to the concepts and the relations in the ontology. Also it provides mechanisms for literal sense changes like type-coercion, metonymy, and similar. Some of these phenomena are presented in the annotation.