Change to Definition of Disability

 A 401(k) plan provides for 100% vesting upon becoming "disabled,' defined as, "a physical or mental condition that makes him unable to engage in any substantial gainful activity and that can be expected to result in death or has lasted or can be expected to last for at least a twelve-month period or results in death." A determination of disability is currently made by the plan administrator. The plan sponsor desires to amend the plan to change the definition of disabled to mean a disability as determined by the Social Security Administration. Would this amendment to the definition of "disabled" under the plan constitute a change to the vesting schedule under Section 411(a)(10) that would require an election to be offered to those participants with 3 years of service? As a side note, the Social Security definition of disability seems to align with the current definition of disability in the plan, so arguably this plan amendment would affect only the party making the determination.

Will the change be prospective?

The amendment would apply to claims filed on or after the date the amendment is adopted.