Electronic laboratory notebooks (ELNs) are more accessible and reliable than their paper based alternatives and thus find widespread adoption. While a large number of commercial products is available, small- to mid-sized laboratories can often not afford the costs or are concerned about the longevity of the providers. Turning towards free alternatives, however, raises questions about data protection, which are not sufficiently addressed by available solutions. To serve as legal documents, ELNs must prevent scientific fraud through technical means such as digital signatures. It would also be advantageous if an ELN was integrated with a laboratory information management system to allow for a comprehensive documentation of experimental work including the location of samples that were used in a particular experiment. Here, we present OpenLabNotes, which adds state-of-the-art ELN capabilities to OpenLabFramework, a powerful and flexible laboratory information management system. In contrast to comparable solutions, it allows to protect the intellectual property of its users by offering data protection with digital signatures. OpenLabNotes effectively closes the gap between research documentation and sample management, thus making Open-LabFramework more attractive for laboratories that seek to increase productivity through electronic data management.