Natco Pharma's intraday chart revealed a sharp spike immediately after the buyback news, with the stock reaching Rs 580 per share on Wednesday, up 2.5 percent from Monday's close. The Indian equity markets were closed on Tuesday due to the Holi holiday.The buyback price is fixed at a 23 percent premium to the prior day's BSE closing price of Rs 566 per share. Natco Pharma shares were trading at Rs 571.50 per share on the Exchange at 12:35 PM today, up Rs 5.35 or 0.94 percent.In an exchange filing, the drugmaker stated that it intends to purchase back 30 lakh shares, or 1.64 percent of its paid-up equity shares."If the equity shares are bought back at a price lower than the maximum buyback price, the actual number of equity shares bought back may surpass the indicative maximum buyback shares but will always be subject to the maximum buyback size," Natco Pharma says.According to a statement, the buyback shall not exceed the maximum buyback size, which equals 5.13 percent and 5.04 percent of the company's total paid-up capital and free reserves, respectively.A buyback committee has also been formed by the company, which comprises Managing Director VC Nannapaneni, Director & Chief Executive Officer Rajeev Nannapaneni, and Director & Executive Vice President (Corporate Engineering Services) PSRK Prasad.When a company buys its own outstanding shares to reduce the number of shares available on the open market can be termed a buyback, which is also known as a share repurchase.