Retirement Plans

I have three 401(k) accounts with various employers.

My current one began <1 yr ago with new employment (comprises 3% of my overall value), a previous one began 6 yrs ago with a previous employer (comprises 79% of my overall value)and the earliest one began almost 11 yrs ago with still another employer (comprises 18% of my overall value). I have been married 14+ yrs .

Is there a difference of how my spouse and I would split that up or is it just 50-50?

You split the amount of retirement saved during the marriage.