AAP leader Sanjay Singh, businessman Sushil Gupta and chartered accountant Narain Dass Gupta here on Thursday filed their nomination for the three Rajya Sabha seats that will fall vacant this month in Delhi.Singh reached the District Magistrate (Central) office at Daryaganj to file the papers atop a truck packed with supporters and playing patriotic songs. Aam Aadmi Party leader Ashutosh accompanied him.Narain Gupta and Sushil Gupta later filed their nomination papers. An alumnus of Delhi University's Shri Ram College of Commerce, Narain Gupta has been on the Board of International Federation of Accountants -- an amalgam of 164 regulatory accounting bodies in 116 countries.Sushil Gupta was formerly with the Congress.Three Rajya Sabha seats from Delhi will fall vacant by the end of this month when the tenure of Congress members Janardhan Dwivedi, Parvez Hashmi and Karan Singh ends. It will be for the first time the AAP, which officially has 66 members in the 70-member Delhi Assembly including some dissidents, will send members to the upper house. The Congress has no presence in the Delhi Assembly.