A: While not exhaustive, this summary should provide some of the basics when it comes to an employee stock option grant at a startup.
When an employee receives stock options, the employee receives the contractual right to purchase shares of company stock at a fixed strike price (e.g., the option to purchase 10k shares of the company's common stock at $1.00 per share - meaning the employee will ultimately have to pay $10,000 to purchase the shares). Options generally vest over 4 years with a 1-year "cliff" (meaning no options vest until 12 months after the vesting commencement date) and then monthly (or quarterly) thereafter. Options generally expire 90 days after an employee leaves the company and there are several ways that vesting may accelerate (e.g. upon sale, change of control, or other liquidity event). Depending on your level/seniority, some of these terms may be negotiable.
It is important to ask about the company's capitalization to understand your "fully diluted" percentage ownership interest. You will want to know the number of options that have been authorized and granted under the plan and whether additional options will be granted in the future. Likewise, you will want to know the company's latest valuation from their most recent 409A report. If the company raises additional equity in the future, that will ultimately dilute (or reduce) your ownership stake. You will want to understand if the company plans to grant you additional options in the future as some employers grant additional options annually (e.g. around your anniversary date) while others do so on an ad-hoc basis or not at all.
In terms of potential risks and benefits, if the company does well in the future and your options are still valid, you might earn some money down the road depending on the difference between your strike and sale prices. There are tax implications to consider depending on the type of option granted (Incentive Stock Options vs. Non-Qualified Options) and whether you exercise your option to purchase and hold your shares for a time in advance of a sale.
Ultimately, you should treat any compensation derived from startup company options as an unexpected windfall. The reality for most startups is that options are never worth anything down the road.
