Possibly all of them given its arguably a rational thing to do. If you look at a list of unicorns, you will see a huge glut of them are valued at precisely 1B.

People say that this is not chance that so many different businesses happen to be worth the same but that they have accepted punitive terms to stretch their valuation to 1B because the press advantages are worth the cost. This effect will also have applied to all the companies now valued above 1B because they played the same game when they were <1B and "reached" to get the label.

We maintain a real-time list of unicorns and regularly have companies reach out requesting to be added.

They're interested enough that they provide paperwork to prove the valuation when we are unable to independently verify.

https://www.cbinsights.com/research-unicorn-companies