Acceleration
Definition
A provision that speeds up your vesting schedule when certain events occur. Single-trigger acceleration means your vesting accelerates upon one event (typically a change of control like an acquisition). Double-trigger acceleration requires two events (change of control AND termination of your employment). Acceleration can be full (100% of unvested shares vest) or partial.
Real-World Example
Your offer includes double-trigger acceleration. The company is acquired (trigger 1), and then you are laid off 3 months later (trigger 2). All your unvested shares immediately vest. Without this provision, the acquirer could fire you and reclaim your unvested equity.
Common Mistake
Assuming all acceleration provisions are the same. Single-trigger acceleration is much more valuable than double-trigger, but also rarer. Many people do not check whether their offer includes any acceleration at all — and most standard option agreements do not include it by default.
Why It Matters
Without acceleration, an acquisition can actually harm employees. The acquiring company can terminate you post-acquisition, and you lose all unvested equity. Acceleration protections are one of the most under-negotiated parts of an offer.
Related Terms
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