A week after markets regulator Sebi asked companies to disclose in detail their estimated and expected losses due to the Covid-19 pandemic, disclosures by some of the leading corporates show that loss of revenue, along with the availability of labour and logistics challenges, top the list of hurdles. Of the about 25 corporates that have disclosed to the exchanges the impact of the Covid-19 pandemic on their businesses, the top ones include Bharat Forge, Titan, Avenue Supermarts (D-Mart), Dabur and L G Balakrishnan.