A company can buy back its shares using various sources, subject to legal and regulatory requirements and its own financial situation. The sources from which a company can buy back its shares include:

Free Reserves: Companies can use their accumulated profits or free reserves to finance a share buyback. These reserves are generated from past profits and can be utilized for this purpose.

Securities Premium Account: The balance in the securities premium account, which is created when shares are issued at a premium, can be used to finance a share buyback.

Proceeds from the Issue of New Shares: If a company issues new shares, particularly at a premium, it can use the proceeds from this issuance to fund the buyback. This method is often used in combination with the share issuance.

Issue of Fresh Equity: A company may raise funds by issuing new equity shares with the specific intention of using the proceeds for a share buyback.

Debt Financing: Companies can take on debt, such as loans or bonds, to finance a share buyback. This approach allows the company to leverage its balance sheet, but it increases its debt obligations.

Cash and Cash Equivalents: Existing cash reserves or short-term investments held by the company can be used to fund a share buyback. Companies with strong liquidity may choose this option.

Sale of Non-Core Assets: The sale of non-core assets or subsidiaries can provide the necessary funds for a share buyback. This approach is often taken when the company wishes to monetize non-strategic holdings.

External Borrowings: Companies may borrow funds externally to finance share buybacks. This can involve taking loans from financial institutions or issuing corporate bonds.

Special Reserves: Some companies maintain special reserves, which can be earmark for specific purposes like share buybacks.

Trust Funds: A company can establish a trust to buy back shares on its behalf. The trust is funded with cash or other assets, and it carries out the buyback transactions.

Internal Accruals: A portion of the company's operating cash flows can be used for share buybacks if the company generates sufficient cash internally.

Convertible Securities: Companies may issue convertible securities (e.g., convertible bonds or preference shares) with the intention of using the funds from conversion to finance a buyback in the future.

The choice of funding source for a share buyback depends on various factors, including the financial position of the company, its capital structure, and the specific objectives of the buyback. Companies must also adhere to legal and regulatory requirements, which can vary by jurisdiction, when conducting share buybacks. Additionally, the decision to repurchase shares should align with the company's strategic goals and capital allocation strategy.