Looks like last year, 160 companies IPO'd in the US and it seems that 2018 is predicted to be an IPO-heavy year [0]. Given that Carta seems to be one of the more mature and heavily capitalized cap table SaaS solutions, ~10% market share doesn't sound unreasonable (and is certainly a great achievement!). If this year is great for IPOs, congrats them on a boom time.

[0]: https://www.ft.com/content/ae9e6500-e69b-11e7-8b99-0191e4537...