Vesting Acceleration

Vesting acceleration is a contractual provision that speeds up your normal vesting schedule so you gain ownership of unvested equity earlier than planned, usually in connection with an acquisition or job loss.

Key Idea

Normally, equity vests over time (e.g., 4 years with a 1-year cliff). Acceleration lets some or all of your remaining unvested shares vest immediately when certain events happen. This is meant to align your equity with the value you helped create, even if the company’s timeline (like an early acquisition) is shorter than your vesting schedule.

Common Types of Acceleration

Single-Trigger Acceleration

• Trigger: Acquisition only.
• Effect: When the company is acquired, some or all of your remaining unvested shares vest immediately.
• Implication: You’re fully or partially vested at closing, regardless of whether you stay or are later terminated.

Double-Trigger Acceleration

• Triggers (both required):
  1. The company is acquired.
  2. You are terminated without cause (or resign for good reason) within a defined period after the acquisition.
• Effect: If both triggers occur, some or all of your remaining unvested shares vest immediately.
• Implication: This is generally more employee-friendly and more acquirer-friendly than single-trigger, because it protects you if you lose your job due to the acquisition, but doesn’t automatically fully vest everyone at closing.

Why Acceleration Exists

Startup exits are unpredictable. You might join expecting to vest over 4 years, but the company could be acquired much earlier. Without acceleration, you’d only keep the portion that has vested by that time and forfeit the rest, even though your work contributed to the company’s full exit value. Acceleration is designed to:

• Better match your equity with the value you helped create.
• Protect you if an acquisition leads to your role being eliminated.

Example

You receive 20,000 shares with a 4-year vesting schedule and a 1-year cliff.

• After 24 months, you’ve vested 10,000 shares (50%).

Scenario 1: No acceleration, company acquired at 24 months

• You keep the 10,000 shares that have already vested.
• The remaining 10,000 unvested shares are forfeited.
• The acquirer may offer a new grant, but it starts from zero.

Scenario 2: Double-trigger acceleration, acquired at 24 months

• Trigger 1: The company is acquired.
• You stay on through the transition.
• After 8 months, your role is eliminated (termination without cause).
• Trigger 2: Termination without cause after the acquisition.
• Result: Your remaining 10,000 unvested shares vest immediately.
• You end up with all 20,000 shares.

Scenario 3: Single-trigger acceleration, acquired at 24 months

• The acquisition itself triggers full acceleration.
• All 20,000 shares vest immediately at closing.
• You are fully vested regardless of what happens to your role afterward.

What to Watch Out For

• Partial vs. full acceleration
• Caps on acceleration
• Replacement equity from the acquirer
• Tax timing

Related Terms

• Double-Trigger Acceleration — Acceleration that requires both an acquisition and a qualifying termination (usually termination without cause or resignation for good reason). Often considered the most employee-friendly structure.
• Single-Trigger Acceleration — Acceleration that occurs upon acquisition alone. This can be less attractive to acquirers because it fully or partially vests employees immediately at closing.
• Cliff Vesting — A period (commonly 1 year) during which no equity vests, followed by a lump-sum vesting of a large portion (e.g., 25% at 12 months). Acceleration is especially important if an exit happens before or shortly after the cliff, because otherwise you might receive little or nothing.