The Sensex has slipped back into the negative zone and is now down 27 points at 15,439.NTPC has soared 2.7% to Rs 186. Tata Motors has rallied over 2% to Rs 706.Cipla, Wipro and ICICI Bank have surged 1.7% each to Rs 183, Rs 473 and Rs 918, respectively.Grasim, Bajaj Auto and Ambuja Cements are up around 1% each at Rs 3,057, Rs 2,310 and Rs 137, respectively.Maruti has dropped nearly 2% to Rs 877.Bharti Airtel and Ranbaxy have slipped 1.3% each to Rs 848 and Rs 401, respectively.Larsen & Toubro and ACC are down 1% each at Rs 2,595 and Rs 1,087, respectively.Out of 2,765 stocks traded so far, 1,523 have advanced, 1,168 have declined and 74 are unchanged.