Single-trigger acceleration means that the unvested shares vest immediately upon the closing of a specified event (e.g., acquisition, merger, IPO), in whole or in part.
Investors will strongly oppose single-trigger acceleration for Founder shares because most often buyers want the Founders to continue to stay with the company for 12 months or more post-sale. Therefore, we generally recommend that the company have double-trigger acceleration on Founder shares.
Language – Modified Single-Trigger: If, at the time of a Change of Control, you remain in Service and the acquiring entity refuses to assume, replace, fully accelerate, cash out at the deal price, or substitute an equivalent award that preserves the intrinsic value of the Option and does not impose a vesting schedule less favorable than the one in effect immediately prior to the closing of the Change of Control, then, subject to the satisfaction of the Acceleration Conditions, effective as of immediately prior to the closing of the Change of Control, the Company will accelerate the vesting of this Option to all of the then-unvested shares subject to this Option (that is, a modified 100% single trigger).
See Stock Option Grant Notice; Form: 151516249.