Startup acquisition: What happens to the stock when you sell your company

Michał Kowalewskiby Michał Kowalewski • 7 min readpublished September 15, 2023 updated December 4, 2023
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The startup world is an ever-evolving arena where new ventures are launched, nurtured to growth, and frequently become acquisition targets.

For everyone involved—be it founders, team members, or investors—the acquisition phase raises a critical question: What becomes of the company's stock? This query is not just financial but also emotional, as the stock often represents years of hard work, investment, and dreams.

This article serves as a comprehensive guide to shed light on this complex subject. It aims to clarify the various outcomes that can occur with your stock during an acquisition, providing valuable insights to help you make informed decisions during this pivotal moment in your startup's lifecycle.

Key takeaways

  1. Types of Acquisitions: Acquisitions can be categorized into cash deals, stock-for-stock transactions, or a mix of both. Each type has its own implications for your stock and taxes.
  2. Factors Affecting Stock: The fate of your stock depends on various factors such as the type of equity you hold, vesting schedules, and special contractual clauses like acceleration or drag-along rights.
  3. Legal and Tax Nuances: The acquisition process involves complex legal and tax considerations, including due diligence, indemnification clauses, and capital gains tax. Professional consultation is highly recommended.

Types of Startup Acquisitions

1. Cash Deals

In a cash acquisition, the acquiring company pays a predetermined amount of money for the startup. This is usually good news for shareholders as they receive a cash payout for their shares. However, it's crucial to understand the tax implications, as this transaction is considered a taxable event.

2. Stock-for-Stock

Here, instead of cash, shareholders receive shares from the acquiring company. This can be advantageous as it avoids immediate taxation. The ratio of old shares to new shares is rarely one-to-one and is determined by the terms of the deal.

3. Mixed Deals

In some cases, the acquisition might involve a combination of both cash and stock. This offers a balanced approach, allowing shareholders to enjoy immediate profits while also investing in the future of the combined entity.

Factors Affecting Your Stock During a Startup Acquisition

When a startup is acquired, the fate of your stock depends on several factors. These factors can vary based on the type of equity you hold, the terms of your employment agreement, and the specifics of the acquisition deal. Here's a more detailed look at these factors:

1. Type of Equity

Common Stock - If you hold common stock, you are generally last in line when it comes to payouts. Preferred shareholders and debt holders usually get paid first. However, if the acquisition price is high enough, common shareholders can still make a significant profit.

Preferred Stock - Preferred stockholders have a priority claim on the assets and earnings of a company. In an acquisition, they are generally entitled to receive their investment back before common stockholders get paid.

2. Vesting Schedule

Cliff Vesting - If your shares are subject to a one-year cliff, and the acquisition happens before you've reached that milestone, you may walk away with nothing unless there's an acceleration clause in your contract.

Gradual Vesting - In cases of gradual vesting, you'll generally be able to cash out the shares that have already vested. Unvested shares are usually subject to the terms of the acquisition agreement.

3. Acceleration Clauses

Some employment contracts include acceleration clauses that immediately vest all or a portion of your unvested shares in the event of an acquisition. There are two main types:

  • Single-Trigger - Your shares immediately vest upon the sale of the company.
  • Double-Trigger - Your shares vest if the company is sold and you are terminated without cause, usually within a year of the acquisition.

These clauses can significantly impact your financial outcome in an acquisition. For example, if you're early in your vesting schedule and your company gets acquired, an acceleration clause can ensure you receive a more substantial payout.

4. Conversion Ratios

In a stock-for-stock acquisition, your existing shares are converted into shares of the acquiring company based on a conversion ratio. For example, a 2:1 ratio means two of your startup shares will convert into one share of the acquiring company. This ratio affects your ownership stake in the new entity and can either strengthen or dilute it.

The type of new stock may also come with different voting rights or dividends. Tax implications can vary, so consulting a tax advisor is crucial. Understanding the conversion ratio is key to assessing the long-term value of your investment in the new company.

5. Holdback

A holdback is another mechanism that acquiring companies use to mitigate risk, but it's different from escrow in its purpose and execution. In a holdback arrangement, a portion of the purchase price is deliberately withheld at the time of the acquisition. This withheld amount is released once certain agreed-upon conditions or milestones are met.

For instance, the holdback might be contingent on the startup reaching specific revenue targets post-acquisition or successfully integrating its technology into the acquiring company's existing systems. If the conditions are not met within a specified timeframe, the acquiring company may keep the holdback amount, reducing the total payout to the startup's shareholders.

6. Escrow

In a startup acquisition, an escrow account is often set up as a financial safety net for the acquiring company. A portion of the purchase price is placed in this third-party account and is held there until specified conditions are met or a certain time passes. This fund is designed to cover any unforeseen liabilities or claims that may arise after the acquisition, such as financial misrepresentations by the startup.

For shareholders, this means that some of the money you're expecting from the sale will be temporarily unavailable. The terms and duration of the escrow are outlined in the acquisition agreement, and the funds are released to shareholders once the escrow period ends without issues.

7. Market Conditions

The overall economic climate can also impact the acquisition deal, including the stock price of the acquiring company in stock-for-stock transactions. Understanding these factors can help you better navigate the complexities of what happens to your stock during an acquisition. Always consult legal and financial advisors to ensure you're making the most informed decisions.

Legal and Tax Considerations During a Startup Acquisition

Navigating the legal and tax maze during a startup acquisition is crucial for both founders and employees. The implications can be complex and long-lasting, affecting your financial health and future investment strategies. Here's a deeper dive into the legal and tax considerations you should be aware of:

Legal Aspects

  • Due Diligence. Before the acquisition is finalized, the acquiring company will conduct a thorough due diligence process. This involves reviewing all legal documents, contracts, intellectual property, and liabilities. Make sure all your paperwork is in order to avoid any complications.
  • Indemnification Clauses. These clauses protect the acquiring company from any future liabilities that may arise from the operations of the startup before the acquisition. As a shareholder, be aware that a portion of the deal's value might be held in escrow to cover these liabilities.
  • Non-Compete and Non-Solicit Agreements. These agreements may restrict you from starting a similar business or soliciting employees from your former company for a specified period post-acquisition.
  • Intellectual Property Transfer. If you have contributed to patents, trademarks, or copyrights, ensure that the transfer of these intellectual properties is clearly outlined in the acquisition agreement.

Tax Considerations

  • Capital Gains Tax. In a cash deal, the lump sum you receive for your shares will be subject to capital gains tax. The rate depends on how long you've held the stock; long-term gains are generally taxed at a lower rate than short-term gains.
  • Stock Options Tax. If you have unexercised stock options, you may have the choice to exercise them before the acquisition closes. This decision has tax implications, so consult a tax advisor to understand the best course of action.
  • Deferred Taxes. In some stock-for-stock transactions, you can defer the capital gains tax until you sell the new shares. However, this depends on the structure of the deal and the tax laws in your jurisdiction.
  • AMT Considerations. If you have Incentive Stock Options (ISOs), exercising them might subject you to the Alternative Minimum Tax (AMT). It's crucial to calculate this beforehand to avoid a hefty tax bill.
  • Earn-Outs and Tax Deferral. Some deals include earn-outs, where additional payment is made based on future performance metrics. These payments are also taxable, and the timing of the tax depends on how the earn-out is structured.
  • State and Local Taxes. Don't overlook state and local taxes, which can add an additional layer of complexity. The tax implications can vary significantly depending on the state in which you and the acquiring company are located.


Startup acquisitions are complex events with multiple variables affecting the stock of the company being acquired. Whether it's a cash deal, a stock-for-stock transaction, or a combination of both, understanding the intricacies can help you make informed decisions.

Startup Finance
Michał Kowalewski

Written by Michał Kowalewski

Writer and content manager at Capbase. Passionate about startups, tech and multimedia. Based in Warsaw, Poland.

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