I have a Plan that is part of a control group with 4 adopting employers. Each adopting employer signed a supplemental participation agreement to "join" the Plan.

Each of these adopting employers has now cuanged their legal name. I've amended the Plan to change the legal name of the Plan and the sponsoring "Employer", but I'm not sure of the best way to change the name of the adopting employers. Should I do new supplemental participation agreements in the new names or just some short amendment type document for each? I don't see this as a Plan amendment, per se. Right now I'm thinking of just doing an "amendment to supplemental participation agreement" for each of the 4 adopting employers.

In my opinion it will be six of one or a half-dozen of the other. Either option should accomplish what you want.