The payment conditions (quit for good reason or involuntary term w/o cause) meet the separation pay exception, but that only covers payments of up to 2x 401(a)(17) amount (so $560,000). The rest (either $40k or $600k, or possibly much more because of bonus) is not within the exception, so treated as a 409A plan. The issue is not exactly potential for manipulation, but whether the payments with respect to each year have fixed payment dates. Also, if public company make sure to comply with 6-month rule for amounts not fitting within separation pay exception.