Purpose - This study aims to investigate whether there exist speculative bubbles in stock prices traded on the Egyptian Stock Exchange. Design/methodology/approach - In this study, to identify the presence of speculative bubbles in stock prices, the authors follow the study of Anderson and Brooks (2014) by applying their model for measuring stocks bubble sizes in addition to extract periods of bubbles of stock prices (heterogeneously and homogenously) using a time series of monthly data for the period from January 2008 to December 2020, the model allows measuring relative bubble sizes of individual stocks using data on stock prices and dividends, the current study uses a sample of 110 stocks traded on the Egyptian exchange which considered the most active in terms of trading volume and liquidity, these active stocks are representative to 14 of different economic sectors of the Egyptian economy. Findings - The empirical results indicate during the study period of the dataset for all heterogenous 110 companies taken together, occurrence of three negative bubbles in their stock prices, further, the dates of these bubbles correspond to specific events happened in the Egyptian economy. In addition to Anderson and Brooks (2014), we extended our analysis making stocks relatively homogenous by grouping them into 14 different sectors in order to study each economic sector separately to reveal which sectors are mainly responsible for arising each bubble, we find that the further analysis can better describe bubbles as few sectors shown more obvious big bubble sizes for each bubble during the study period, only six sectors in 2008-2009, three in 2011-2012, and two in 2016-2017, as they mainly responsible for the initial arising of bubbles in the whole market, while other sectors haven’t witnessed any bubbles during the research period. Originality/value - This study contributes to previous research in bubble literature, our study is the first that reveals negative bubbles of stock prices in the Egyptian Exchange in addition to reveal which stocks and sectors are responsible for bubbles occurrence in each period, number of companies lacks investments although they considered an opportunity to increase investors’ returns, because during the study period stocks’ fundamental values are shown higher than market prices, also few sectors are exposed to outflows, although these companies continuously distribute cash dividends, investors extensively selling certain stocks causing sudden outflows which in turn lead to bubbles, so these companies should exert more efforts to inform investors of the true values of their stocks, the central bank of Egypt should encourage investments through taking decisions controlling sustainable currency depreciation to encourage foreign investors to invest their money in the Egyptian exchange.