A company can buy back its shares in the following manners:
From the existing shareholders on a proportionate basis through the tender offer
From open market through:-
Book building process
Stock exchange
From odd lot holders
A company may buyback its shares without any resolution of the shareholders, to the extent of 10% of the paid up equity capital and reserves. If a company intends to buyback its shares to the extent of 25% of its paid up capital and reserves, then the same has to be approved by Shareholders Resolution as specified in Section 77A of Companies Act, 1956
Listed companies are required to inform the stock exchange of general meetings and resolutions passed there. Information on companies offering to buyback shares may be obtained from the stock exchanges. After a buyback offer document or public announcement is filed with SEBI, it issues a press release and the offer document is put on the SEBI website in the primary market page under the head “buyback”