Web based applications offer a mainstream channel for businesses to manage their activities. We model such business activity in a grammar-based framework. The Backus Naur form notation is used to represent the syntax of a regular grammar corresponding to Web log patterns of interest. Then, a deterministic finite state machine is used to parse Web logs against the grammar. Detected tasks are associated with metadata such as time taken to perform the activity, and aggregated along relevant corporate dimensions. Categories and Subject Descriptors H.4.1 [Office Automation]: Desktop Publishing, Groupware, Time Management, Workflow Management,. General Terms: Design, Experimentation, Measurement.