In one brutal hour, shares of Indian IT companies crashed today, wiping out over Rs. 50,000 crore in the market value of top companies, after a bill was introduced in the US House of Representatives calling for more than doubling the minimum salary of H-1B visa holders to $130,000, from the current $60,000. A sharp rise in minimum salary will make it difficult for Indian IT companies to hire employees on H-1B visas to work on projects in the US, which contributes around 60 per cent of the export revenues of the Indian IT sector.