The article explores the semi-monthly effect in stock returns on the Bombay Stock Exchange. The researchers analyzed data from five sectoral indices over a 10-year period. They used two different approaches to examine if there was a difference in returns between the first and second halves of the month. The results showed that there was no significant semi-monthly effect in most sectoral indices, except for the BSE Auto Index, which did show a significant difference in returns between the two halves of the trading month.