You do not have to assign the stocks to the remaining shareholders. These stocks will remain the the corporation and can be reissued to some other stockholder joining into the corporation.
If you want, the corp can give these as stockdividend and hence you can transfer it to the 2 remaining shareholders. But, you do not have to do so.
Earlier the stockholders were 100, 100, 100 share owners .....do the sharing was 1/3rd
now they will have 100, 100 shares ....so they will be 1/2 owners.
If you assign 50 shares to each of them-
they will have 150, 150 shares....so in essence they will be 1/2 owners only...
So does not make a difference whether you assign the shares or hold it as treasury stock in the S Corp.
Let me know if you have any question.
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