Is it atypical for founders to vest more than 25% of their equity after one year? What are the potential issues?

The default standard, certainly in the Silicon Valley region, is 25% after one year of service, then followed by monthly vesting over 3 years.  I typically advise founders to start the vesting when they began working on the company, because that is the most defensible position when dealing with an investor that wants to change the vesting.  So, I would say that the most typical arrangement is 25% after one year of service to the company.  Other arrangements might be appropriate under different circumstances, it's just a matter of judgment and circumstance.

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