A start-up company would like to modify the vesting schedules for the equity grants to employees. The final vesting dates for some employees would move out a year or two, and some in a year or two. Are there any tax implications I need to be aware of prior to implementing these changes? Also, all employees filed 83(b) elections, and this change will effect the "latest date property is subject to forfeiture". Does anything need to be updated with these or similar documents?