Stock Purchase Agreement: Buying the Company Behind the Shares

A stock purchase agreement is a contract in which a buyer acquires shares from existing shareholders or from a company issuing new stock.

In a stock purchase, the buyer is not just buying paper; the buyer is taking ownership of the company behind those shares, including risks that never appear on a stock certificate. The same document type covers both a straightforward acquisition of an existing owner's shares and an investor's purchase of newly issued stock. Price, ownership percentage, and the transfer of title are only the starting terms. The heavier work lies in allocating the company's hidden risks.

The core difference is that a stock buyer inherits the company's liabilities, while an asset buyer can often leave many of them behind.

Buying stock usually carries the company's contracts, tax history, and legal exposure along with it, whereas an asset deal lets the buyer select specific assets and assumed liabilities. Stock deals may need fewer third-party consents, though change-of-control clauses can still be triggered, and the tax treatment differs for both sides. The table compares the common structures.

Confirming clean ownership means checking the company's capitalization, the seller's title, and any restrictions on transferring the shares.

The agreement should verify the seller's ownership and authority, the fully diluted capitalization, the stock ledger, and the absence of liens on the shares. Private company stock is frequently tied up by a shareholders' agreement, bylaws, or investor rights that impose a right of first refusal, co-sale or drag-along rights, or a board consent requirement. Missing one of these can block or unwind the transfer. Clearing them is part of confirming the shares can actually change hands.

Due diligence examines the company's finances, taxes, contracts, and legal exposure so the buyer knows what it is inheriting.

A thorough review covers debt, tax positions, pending or threatened litigation, intellectual property ownership, employment issues, key customer contracts, and regulatory compliance. Findings are typically reflected in disclosure schedules and in the price, indemnity, or closing conditions, and coordinated deal support keeps the process organized. What diligence reveals often reshapes the terms that follow. Skipping it is how buyers discover problems only after they own them.

Representations and warranties are the factual promises each side makes about the company, and closing conditions are what must be true before the deal completes.

The seller typically represents ownership of the shares, the accuracy of financial statements, tax status, litigation, intellectual property, and the absence of undisclosed liabilities, while the buyer represents its authority and funding. Closing conditions can include board and shareholder approvals, third-party and regulatory consents, financing, and no material adverse change in the business. These provisions, common across M&A and sales and acquisitions work, define the deal's guardrails. If a representation is wrong, the indemnification terms decide the consequence.

Yes, buying or selling stock is a securities transaction, so the deal must be registered or fit within an exemption.

Under the Securities Act of 1933, an offer or sale of securities generally must be registered unless an exemption applies, and private deals commonly rely on exemptions such as Regulation D and Rule 506, often limited to accredited investors. Shares acquired privately are usually restricted securities, whose resale is limited by rules such as Rule 144, and issuers filing under Regulation D handle a private placement rather than a public offering, which connects to venture capital financing practice. A financing where a company issues new stock is often documented as a securities purchase agreement rather than a stock purchase of existing shares. Confirming the right exemption is part of sound securities compliance.

Closing exchanges the price for the shares and the transfer documents, and post-closing steps record the new ownership.

After closing, the company updates its stock ledger, cancels or reissues certificates or updates uncertificated records, applies any restrictive legends, and coordinates with a transfer agent, while price adjustments or earnouts may still be settled. On the sell side, planning for these steps mirrors what careful divestiture work requires. A template agreement rarely fits a specific company's capitalization, shareholder documents, securities status, and diligence findings. Before signing a stock purchase agreement of any real value, have counsel tailor the terms and confirm the closing mechanics.

Generally yes. In a stock purchase, you acquire the company itself, so its debts, contracts, tax history, and legal exposure usually remain with the business you now own. That is a key difference from an asset purchase, where a buyer can often leave many liabilities behind. Due diligence and indemnification address this risk.

In a stock purchase, the buyer acquires the company's shares and inherits its liabilities. In an asset purchase, the buyer selects specific assets and assumed liabilities, often leaving others with the seller. Stock deals may need fewer consents but carry more inherited risk, while asset deals involve more transfer steps and different tax treatment.

The agreement should verify the seller's title, the company's capitalization and stock ledger, and the absence of liens on the shares. It should also confirm compliance with any transfer restrictions, such as a right of first refusal, board consent, or shareholder agreement. These checks ensure the shares can lawfully change hands.

They are factual promises about the company and the deal. A seller typically represents share ownership, accurate financial statements, tax status, litigation, intellectual property, and undisclosed liabilities, while a buyer represents authority and funding. If a representation proves false, the indemnification provisions determine who bears the resulting loss.

They allocate post-closing risk. A cap limits the seller's total indemnity exposure, a basket sets a threshold that claims must exceed before they are payable, and an escrow reserves part of the price to cover claims. A survival period fixes the claim window, and a fraud carveout usually removes these limits for deception.

Yes. Stock is a security, so its sale must be registered or qualify for an exemption under the Securities Act. Private deals often rely on exemptions like Regulation D and Rule 506, and privately acquired shares are usually restricted, limiting resale under rules such as Rule 144. Structuring the exemption correctly matters.

They can. Private company shares are frequently subject to shareholder agreements, bylaws, or investor rights that include a right of first refusal, co-sale or drag-along rights, or board consent requirements. If these apply, the seller may need to satisfy or clear them before transferring the shares, so they should be reviewed early.

For any significant deal, tailored legal work is worth it. A template rarely accounts for the company's capitalization, shareholder documents, securities law status, and diligence findings. Counsel can structure the representations, indemnification, closing conditions, and securities exemption, which often protect far more value than the fee involved.