Information and communication technologies are inspiring and enabling entrepreneurial endeavours yet our understanding of how entrepreneurial opportunities are discovered, especially influenced by the web technologies, is limited. The advent of web technologies (especially Web 2.0 and Web 3.0) has enabled the creation of internet giants such as Facebook and Twitter on one hand, while empowered the existing online businesses such as Amazon and eBay on the other. However, there is limited research that investigates the role of web technologies for entrepreneurial opportunities discovery (EOD). The findings of a systematic literature review reveal that prior EOD research has mostly investigated different factors such as prior knowledge, social capital and systematic search in isolation. Most of these studies did not investigate the role of technology in EOD indicating a dearth of research. The study used qualitative multiple case studies research methodology including semi-structured interviews, informal observations and archival review to collect data. The qualitative case study methodology was chosen because little was known about the phenomenon under investigation, and the purpose of the study was to develop a theory of entrepreneurial opportunity discovery in the context of web technologies. The research findings revealed several factors that influence entrepreneurial opportunity discovery in technology-based organisations and shed light on the enabling role of web technologies for EOD. The extensive data and information accumulated on the web can be exploited by companies to find entrepreneurial opportunities. The findings of present research can stimulate and encourage the use of web technologies for EOD, which has so far not been used to its full potential.