An offer letter states the role, the pay and the start date. Almost everything else — the bonus plan, the equity agreement, the handbook, the leave policy — is incorporated by reference in a single line, and those documents can usually be changed without your agreement. The most consequential things in an offer are frequently in what it points at rather than what it says.
The sentence to look for
Some version of “subject to the terms of the applicable plan documents and company policies”. That line is doing a great deal of work. It brings in the bonus plan, the equity agreement, the handbook and the leave policy, most of which you have not seen and most of which the employer can amend unilaterally.
Asking to see the ones that carry money — the bonus plan and the equity agreement — before accepting is entirely reasonable and frequently reveals terms the letter does not hint at.
At-will, and what it actually means
In most US employment the letter will say the relationship is at-will and can be ended by either party at any time. That is standard and not a red flag. What is worth reading is whether anything in the letter appears to contradict it — a stated term, a guaranteed bonus — because those create ambiguity rather than protection.
The things that should be in writing and often are not
The bonus target and how it is assessed. The vesting schedule and the exercise window. Whether the signing bonus is repayable and on what terms. The review cycle. Any agreement about remote work or location, which matters enormously and is very often verbal.
Anything agreed in conversation and absent from the letter should be added to it. Not because anyone is acting in bad faith, but because the person who agreed it may not be there in a year and the letter will be.
Restrictive covenants
Non-compete, non-solicit and assignment-of-inventions clauses either sit in the letter or in a document it references. Their enforceability varies enormously by state and some are unenforceable outright, but an unenforceable clause you have signed still has to be argued about, which is not free.
Read them before signing rather than after, because afterwards is when they are expensive.
The practical approach
Ask for every document the letter references. Read the bonus plan and the equity agreement properly. Get anything verbal added. And if a term matters enough that you would not take the job without it, it belongs in the letter rather than in an email from a recruiter.
Common questions
What does an offer letter usually leave out?
The bonus plan, the equity agreement, the handbook and the leave policy. They are incorporated by a single reference and most can be amended without your agreement.
Should I ask to see the plan documents?
Yes, at least the bonus plan and the equity agreement, since those carry money. Asking before accepting is ordinary and frequently reveals terms the letter does not hint at.
Is at-will employment a red flag?
No, it is standard in most US employment. What is worth reading is whether anything in the letter contradicts it, since that creates ambiguity rather than protection.
What if something was agreed verbally?
Get it added to the letter. Not because of bad faith, but because the person who agreed it may not be there in a year and the letter will be.
Do non-competes matter if they are unenforceable here?
An unenforceable clause you have signed still has to be argued about, which is not free. Read them before signing rather than after.