When your company is acquired, what happens to your unvested equity generally comes down to two terms already sitting in your grant documents: single-trigger acceleration (unvested shares vest automatically at closing — rare) or double-trigger acceleration (shares vest only if the deal closes AND you're terminated within a set window afterward, often 12 months — the more common structure). Your 401(k) will typically either be merged into the acquirer's plan or terminated with a 60–90 day window to roll it over, and most acquirers continue your current health plan through the end of the calendar year before switching you to theirs. The acquisition announcement is a sentence; the fine print runs to thousands of pages, and most of it is decided weeks before you hear about it. The specifics depend on your situation, and these rules and figures can change.
What happens to your equity, 401(k), and health coverage?
An acquisition generally touches three things at once, on three different clocks. Unvested equity is governed by the acceleration language already sitting in your grant documents — single-trigger or double-trigger — and if neither applies, the shares typically convert to the acquirer's equity on a similar schedule whose terms may differ. Vested but unexercised options are handled by the deal documents, which usually specify a cash-out at the deal price minus strike, a conversion to acquirer options, or a forced exercise window. Your 401(k) is generally either merged into the acquirer's plan or terminated with a window to roll the balance over. Health coverage is usually the slowest to change, since most acquirers continue the current plan through the end of the calendar year. The specifics depend on the deal and on your situation. Taking each in turn:
1. What happens to your unvested equity?
This is generally governed by two terms in your grant documents, and your specific agreement may differ:
- Single-trigger acceleration: Unvested shares vest automatically on the closing date. Rare; favorable to you.
- Double-trigger acceleration: Unvested shares vest only if (a) the acquisition closes AND (b) you are terminated within a defined window afterward (often 12 months). This is the more common structure.
If neither applies, unvested shares typically convert to the acquirer's equity on a similar vesting schedule — but the new schedule may have different terms.
2. What happens to vested but unexercised options?
For ISOs and NQSOs that have vested but not been exercised, the deal documents will usually specify one of: cash-out at the deal price minus strike, conversion to acquirer options at an equivalent value, or a forced exercise window. It often helps to read the disclosure carefully, since the treatment varies by deal.
3. What happens to your 401(k)?
Two paths are common: the acquirer merges your plan into theirs (your balance moves; investment options change), or the acquirer terminates your plan and gives you 60–90 days to roll over. The IRS generally treats a direct rollover to the acquirer's plan or to an IRA as tax-free, while a cash-out is generally treated as a taxable distribution. Your plan's specific terms and timeline may differ.
4. What happens to health coverage?
Most acquirers continue your current health plan through the end of the calendar year, then transition you to their plan at the next open enrollment. Things many people watch for: a deductible reset mid-year (some transitions credit your prior deductible, some don't), and network changes that affect your existing doctors. The specifics depend on the plans involved.
When does an acquisition work in your favor?
An acquisition tends to work in your favor when the deal terms and your own position happen to line up. The clearest case is double-trigger acceleration combined with being part of the redundancy round, since some people end up receiving both severance and accelerated equity. A second is price: when the deal price sits above the strike price on your options and you have held them long enough for favorable tax treatment, the event turns paper into something worth having. A third is the benefits comparison, which people sometimes overlook — a higher 401(k) match, a richer health plan, or a larger PTO accrual can offset a good deal of disruption. A fourth is a retention bonus offered to keep you through integration, which is common at the manager-and-above level. Whether any of these apply depends on your grant and on the deal. The upside cases people describe:
- Double-trigger acceleration plus a place in the redundancy round — some people receive both severance AND accelerated equity.
- A deal price above the strike price on your options, held long enough for favorable tax treatment.
- A materially better benefits package (higher 401(k) match, richer health plan, larger PTO accrual).
- A retention bonus through integration — common at the manager-and-above level.
When should you be cautious?
The cautious cases generally involve unvested equity, a lockup, or a deadline that runs quietly while everyone is reading the announcement. If you hold unvested shares and your grant has no acceleration clause, the acquirer can generally re-vest you on their own schedule, and that schedule is sometimes worse than the one you had. If a public acquirer is converting your private-company shares into public ones, there may be a lockup period before you can sell — often six months — which matters a great deal if you were counting on the money sooner. And if the acquirer terminates the 401(k) plan, the rollover window is finite; the IRS generally treats a forced distribution as something that can trigger taxes and penalties. Your grant's terms and your plan's window may differ. The situations people most often watch for:
- Unvested equity with no acceleration clauses — the acquirer can re-vest you on their own schedule, which is sometimes worse.
- Private-company shares converting to public shares — there may be a lockup period (often 6 months) before you can sell.
- A terminated 401(k) plan with a missed rollover window — the IRS generally treats a forced distribution as something that can trigger taxes and penalties. Your plan's window may differ.
What should you do in the first 30 days?
The first 30 days are mostly about gathering documents while the people who can answer questions are still in their seats. The grant documents come first, because the acceleration language inside them decides what happens to unvested shares, and it often helps to record vested and unvested balances as of the announcement date rather than reconstructing them later. The 401(k) is next: the current balance and contribution rate are worth writing down before any merge or termination. Health coverage records matter for the same reason, since a mid-year plan change can reset a deductible and some transitions credit the old one while others don't. Knowing who the integration contact in HR is tends to shorten every later question. People who are senior or hold significant equity often consult an equity-comp CPA before the closing date. What people commonly do:
- Find your grant documents and locate the acceleration language.
- Confirm your vesting status (vested vs unvested) as of the announcement date.
- Document your current 401(k) balance and contribution rate.
- Note the year-to-date deductible and out-of-pocket totals on your current health plan.
- Identify the integration point of contact in HR.
- Many people who are senior or hold significant equity consult an equity-comp CPA before the closing date.
What should you ask HR or the integration team?
The useful questions are the ones that pin down dates and treatment rather than intentions. The closing date is the anchor, because some things generally change that day and others change at the end of the calendar year, and knowing which is which makes the rest of the timeline readable. Equity is the second question — whether vested shares are cashed out, exchanged for acquirer shares, or rolled into new options — since each path carries different tax and timing consequences. The 401(k) question is whether the plan will be merged or terminated and on what timeline, because a termination starts a rollover window. Health coverage comes down to whether the deductible you have already paid this year carries over or resets. Retention bonuses are worth asking about directly. Answers depend on the deal. The questions people commonly bring:
- What is the exact closing date, and what changes that day vs at end of year?
- Will my vested equity be cashed out, exchanged for acquirer shares, or rolled into new options?
- Will my 401(k) plan be merged or terminated, and what's the timeline?
- Will my deductible-year-to-date carry over, or does it reset?
- Is there a retention bonus offered for my role?
Under the federal securities laws, the SEC generally requires public acquirers to file detailed disclosures, so the deal terms that affect your equity are often a matter of public record — see SEC investor education on mergers and acquisitions (affiliate link — OffbookHR may earn a commission if you buy through this link. It does not affect ranking.). Because the IRS rules and figures around 401(k) rollovers can change, many people confirm the current treatment at the source — the IRS explains rollover treatment in Rollovers of Retirement Plan and IRA Distributions (affiliate link — OffbookHR may earn a commission if you buy through this link. It does not affect ranking.).