after india's decision to demonetise ₹500 and ₹1000 rupee notes on 8 november 2016, various authorities noticed a surge in shell companies depositing cash in banks, possibly in an attempt to hide the real owner of the wealth. in response, in july 2017, the authorities ordered nearly 2,000 shell companies to be shut down while securities and exchange board of india (sebi) imposed trading restrictions on 162 listed entities as shell companies. a high-level task force found that hundreds of shell companies were registered in a few buildings in kolkata. many of those were found to be locked, with their padlocks coated in dust and many others which had office space the size of cubicles.