---
title: "What Is Acceleration (Double Trigger)?"
term: "Acceleration (Double Trigger)"
description: "Double-trigger acceleration means unvested equity vests only when two conditions occur—typically a change of control plus a qualifying termination such as being fired without cause."
date: 2026-07-25T00:00:00.000Z
updated: 2026-07-25T00:00:00.000Z
topics: ["equity", "deal-terms"]
source: https://venturecapitaltracker.com/glossary/double-trigger-acceleration
---

# What Is Acceleration (Double Trigger)?

> Double-trigger acceleration means unvested equity vests only when two conditions occur—typically a change of control plus a qualifying termination such as being fired without cause.

**Double-trigger acceleration** speeds up vesting of unvested equity only when two defined events happen—most often a company sale combined with involuntary termination without cause.

## How it works

Standard option and RSU agreements vest over four years. In an acquisition, the buyer may not want to honor every remaining tranche automatically—that would pay departing employees for years they will not work. Double trigger splits the difference.

Trigger one is usually a change of control: merger, asset sale, or majority stock transfer. Trigger two is commonly termination without cause or a material reduction in role within twelve to eighteen months after close. If both fire, the specified percentage of unvested equity accelerates—often 50% or 100%, depending on the plan.

Negotiations appear in term sheets, employment agreements, and merger docs. Boards balance employee retention with acquirer demands for clean cap tables.

## Why it matters

- **Founders:** You may negotiate double trigger for yourself and executives while accepting single trigger limits for the broader pool to keep deals viable.
- **Operators:** Read your grant agreement before a sale rumor starts. The difference between zero acceleration and full acceleration can be life-changing on a modest exit.
- **Investors:** Acquirers diligence acceleration provisions. Surprises here can delay or reprice deals.

## Common mistake

Assuming any acquisition automatically vests all unvested equity. Without acceleration language, a buyer typically assumes unvested options and may cancel them at close unless replaced with new buyer grants.

## Related ideas

Compare [single-trigger acceleration](/glossary/single-trigger-acceleration), change-of-control definitions, and retention bonuses in M&A.

## FAQ

### What is double-trigger acceleration in simple terms?

Your unvested stock or options do not automatically vest when the company is sold. They vest if the company is sold and you lose your job—or meet another second trigger defined in your agreement—within a set period after the deal.

### Why does double-trigger acceleration matter?

Acquirers prefer it because key employees stay motivated to earn remaining equity. Employees prefer it because a layoff after a merger still unlocks unvested shares that would otherwise disappear.


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Source: https://venturecapitaltracker.com/glossary/double-trigger-acceleration