This research examines the relationship between Big Data and competition law. Initial findings reveal that accumulating personal information through data collection and acquisition methods benefits consumers considerably. Free of charge, fast and personalised services and products are offered to consumers online. Collected data is now an indispensable part of online businesses to the point that a new economy, a data-driven sector, has emerged. Many markets such as the social network, search engine, online advertising and e-commerce are regarded as data-driven markets where the utilisation of Big Data is a requisite for the success of operations. However, on the other side of the medallion, the accumulation and utilisation of data bring competition law concerns since they contribute to market power in the online world. Therefore, a few technology giants have gained unprecedented market power due to the Big Data accumulation, indirect network effects and the creation of online ecosystems. The sector players such as Google, Amazon and Facebook have established a strong market presence and dominance in their respective markets. As technology giants have billions of consumers worldwide, data-driven markets are truly global. In these data-driven markets, technology giants abuse their dominant positions. However, the current competition law tools seem ineffective in addressing market power and assessing abusive behaviour related to Big Data. To address this challenge, a novel approach to the data-driven sector is developed through the application of competition law rules. The novel approach proposed by this research justifies that the current and potential conflicts can be mitigated by extending the competition law assessment beyond the current competition law tools. Thus, the need for a modernised and unified approach to the Big Data related competition issues is identified. Ultimately, this research contributes to EU Competition Law by promoting new legal tests in addressing the market power of technology giants and assessing abusive behaviour in data-driven markets. Additionally, the need for cooperation between competition and data protection authorities is also nuanced.