A Share Purchase Agreement (SPA) — also known in Australian corporate practice as a Share Sale Agreement — is a legally binding contract that governs the transfer of shares in an Australian company from a seller to a buyer. It is the primary transaction document used in any share sale, whether a founder exits a small proprietary company, a majority shareholder sells to a strategic buyer, or one business acquires another through a share acquisition rather than an asset purchase.

In Australia, companies are incorporated and regulated under the Corporations Act 2001 (Cth), a federal statute administered by the Australian Securities and Investments Commission (ASIC). When shares in an Australian company change hands, the transfer must comply with both the Corporations Act and the company's own constitution. The SPA provides the contractual framework governing the entire sale process: from the agreement on price and completion mechanics, through to the warranties and representations that the seller provides about the company and the shares.

A well-drafted Australian SPA addresses several important legal and tax matters that distinguish it from share sale agreements in other jurisdictions. First, stamp duty is a state and territory tax in Australia, and the liability to pay duty on a share transfer — and the applicable rate — depends on the nature of the company's assets and the jurisdiction in which the transaction is effected. Second, the capital gains tax (CGT) framework under the Income Tax Assessment Act 1997 (Cth) (ITAA 1997) applies to the seller's realisation of the shares, and the SPA should include appropriate CGT provisions and disclosures. Third, the constitutional transfer restrictions and ASIC notification obligations that apply under the Corporations Act must be addressed in the completion mechanics.

This template is suitable for the sale of shares in Australian proprietary companies (Pty Ltd) and public companies and is governed by the laws of the Australian state or territory selected by the parties. It covers all essential provisions for a simple to moderate complexity share transfer: the parties and target company details, the number and class of shares, the purchase price in Australian dollars, completion obligations, stamp duty allocation, seller warranties with appropriate time limits, an optional tax indemnity, and general provisions including governing law and electronic execution.

A Share Purchase Agreement is required in Australia whenever a shareholder sells or transfers shares in a company to another person or entity for value. The most common situations include the following.

Business acquisitions: when one company or individual acquires all or a controlling interest in another company through share purchase rather than an asset purchase. A share acquisition allows the buyer to acquire the entire legal entity, including all assets, contracts, employees, and liabilities — but also all undisclosed liabilities, which is why warranty protections are critical.

Founder or co-founder exits: when one of the founders of a start-up or small business wishes to exit, the remaining founders or new investors typically purchase the departing founder's shares under a formal SPA. The SPA is particularly important in these circumstances to record the agreed price and any post-completion obligations such as non-compete and non-solicitation covenants.

Investor buy-outs: when an angel investor, private equity firm, or other financial investor liquidates their stake in a portfolio company, the SPA records the agreed exit price, any representations about the shares, and the mechanics of the buy-out.

Management buy-outs (MBOs): when the management team of a company acquires the shares from the existing owner, often with the assistance of third-party debt financing. The SPA in an MBO context must address completion conditions relating to the availability of financing.

Employee share plan exits: when an employee who holds shares under an employee share plan or employee share scheme (ESS) exits the company and their shares are purchased by the company or remaining shareholders.

Succession planning: when a business owner transfers shares to family members, a family trust, or a business successor as part of an estate plan or business succession strategy.

In all of these situations, a formal written SPA is essential to record what the parties have agreed and to protect both buyer and seller against future disputes about price, warranties, and completion obligations. An undocumented or informally documented share transfer creates significant legal and commercial risk for both parties.

A Share Purchase Agreement for use in Australia should contain several key provisions that reflect the specific requirements of Australian company law, taxation law, and commercial practice.

Parties and Target Company: The SPA should clearly identify the seller and the buyer by their full legal names and addresses, and identify the target company by its full registered name, Australian Company Number (ACN), and state of incorporation. Where the seller or buyer is a company, the agreement should be executed in accordance with section 127 of the Corporations Act (execution by two directors, or a director and company secretary, or by a sole director who is also the company secretary).

Shares Being Transferred: The SPA must precisely identify the shares being sold: the number, class (ordinary, preference, etc.), and any distinguishing features. The purchase price must be stated in Australian dollars, including the total price and the price per share.

Completion Mechanics: The SPA must specify what each party is required to do at completion. The seller must deliver a duly executed instrument of transfer, the share certificate(s), and any board or shareholder approvals required under the Corporations Act or the company's constitution. The buyer must pay the purchase price in the agreed manner. Post-completion, the buyer must procure registration of the transfer in the company's register of members and notification to ASIC.

Stamp Duty Allocation: Stamp duty is a state and territory tax in Australia, and the SPA should expressly allocate the obligation to pay stamp duty. In most ordinary share transfers, the buyer bears stamp duty. However, if the company holds significant land assets, landholder duty may apply under the Duties Act 1997 (NSW) or equivalent legislation in other states.

CGT and Tax Provisions: The seller's capital gains tax position must be addressed. The purchase price stated in the SPA forms the seller's capital proceeds for CGT event A1 under section 104-10 of the ITAA 1997. The SPA should include CGT warranties from the seller and, in more complex transactions, a detailed tax indemnity protecting the buyer against pre-completion tax liabilities of the company.

Seller Warranties and Limitation of Liability: The seller should give clear warranties about title to the shares and the financial condition of the company. Warranty periods should be carefully defined: 18–24 months for general warranties and up to 7 years for tax warranties aligned with the ATO's standard amendment periods.