Participation is forced

[gjmulhol]

Right now, participation is not an option. If there is a liquidation preference, all shares are participating preferred. There should probably be an option for this because right now <50% of deals are getting participation terms.

[dlopuch]

Agree, probably the biggest omission in the first version.

Making this an option allows mixing participation between rounds, where the math gets a bit tricky. See discussion towards the end of the top comment thread here: https://news.ycombinator.com/item?id=10346585