Your startup is worth 100.  So what is 51% of it worth?
notaddicted: Good Question.It depends on whether someone is trying to buy the 51% or the 49%Selling the 49%: 49 by what I assume the definition of "worth" to be.Selling the 51%:If: You think the buyer can run the company better than you
Then: 51If: You think the buyer can run the company tolerably well
Then: 60
- Extra money to account for loss of control. Note that now the $$$ worth of the company will be changed such that the new worth is 117If: Don't think the buyer can run the company
Then: Forget it, no price
Unless: You need to sell. Then I guess negotiate what you can get.EDIT: I guess this is basically a formula based on the expected future worth of the company, but I can't think of the expression at the moment.