How many shares should I issue when incorporating?

There is a difference between "authorized" shares and "issued" shares.

Authorized shares is set forth in the charter and is the maximum number that can be issued until changed by shareholder vote. 10M is a common number.

Issued shares are the number that are issued at any time. I typically issue about 3-6M of the shares to the founding team depending on the number of founders. The rest are reserved for option pool and other potential issuances.

The actual numbers don't matter much in practice since the percentages don't change, but using larger numbers allows you to make more granular equity grants, allows you to make grants with larger numbers of shares, and keeps the option price low.

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