Bitcoin is an established virtual currency well known for enabling affordable and efficient transfers of money between individuals and entities. With its market cap of over $7 billion and hundreds of thousands per day, the Bitcoin currency has become popular enough for offenders to be able to hide among its users when they purchase illicit goods and services online or need to receive extortion payments. The aims of this presentation are twofold. The first is to present an open-source tool developed by the panelists that analyzes all of the Bitcoin transactions and regroups Bitcoin addresses based on their incoming and outgoing transactions. This allows for a more accurate mapping of individuals' online activities no matter how many Bitcoin addresses they are using. The tool, as well as a database of all nodes identified by the tool, will be released on the day of the conference. The second aim of this presentation is to provide real world use cases for the tool to better understand online illicit activities. To do so, David and Mathieu will present two case studies that will follow the evolution through time of the revenues generated by online illicit groups and the strategies they used to manage the incoming bitcoins. This talk will be of interest to attendees looking to better understand how the Bitcoin currency works and the attacks that can be used to de-anonymize Bitcoin users. A live demonstration will explain how the open-source tool works and the strategies that could be used to preserve one's anonymity in the Bitcoin network.