Vesting acceleration is a provision that speeds up how much of a person’s unvested equity becomes theirs, typically triggered by specific events like the company being acquired or the person being terminated without cause. Without it, a normal vesting schedule just keeps ticking along on its original timeline no matter what happens to the company.
The two common types of acceleration
Single-trigger acceleration vests a portion or all of someone’s remaining equity automatically when one specific event happens, most often an acquisition. Double-trigger acceleration requires two events to both occur, typically an acquisition and the person also being terminated or having their role significantly changed afterward. Double-trigger is far more common in real deals, since investors and acquirers generally resist single-trigger provisions that could let a founder walk away fully vested immediately after a sale closes.
Why acquirers push back on single-trigger acceleration
An acquiring company usually wants key people to stay and keep contributing after the deal closes, and full acceleration on the acquisition alone removes any financial incentive for someone to stick around afterward. Double-trigger acceleration solves this by only kicking in if the person is actually let go or meaningfully demoted post-acquisition, preserving the incentive to stay while still protecting them if the acquirer decides not to keep them.
Why founders negotiate for it upfront
Founders and early employees often negotiate acceleration provisions into their equity agreements before any acquisition is even a possibility, since it’s much harder to negotiate favorable terms in the middle of a deal when leverage has shifted. Having clear acceleration terms in place from the start protects against a scenario where a new owner pushes someone out shortly after buying the company, before their equity has meaningfully vested.
Frequently asked questions
What’s the difference between single-trigger and double-trigger acceleration?
Single-trigger accelerates vesting on one event, usually an acquisition. Double-trigger requires both an acquisition and a termination or role change afterward.
Which type of acceleration is more common in real deals?
Double-trigger acceleration is more common, since acquirers generally resist provisions that remove people’s incentive to stay after a deal closes.
When should acceleration terms actually be negotiated?
Before any acquisition is on the table, since negotiating leverage is much stronger upfront than in the middle of an active deal.
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