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What to consider before buying (exercising) a family member's private company employee stock options, about to expire?
First, you mentioned your brother-in-law has "$100,000 in stock options (fully vested)". Do you mean his exercise cost would be $100,000, i.e. what he'd need to pay to buy the shares? If so, then what might be the estimated value of the shares acquired? Options having vested doesn't necessarily mean they possess value, merely that they may be exercised. Or did you mean the estimated intrinsic value of those options (estimated value less exercise cost) is $100,000? Speaking from my own experience, I'd like to address just the first part of your question: Have you treated this as you would a serious investment in any other company? That is, have you or your brother-in-law reviewed the company's financial statements for the last few years? Other than hearing from people with a vested interest (quite literally!) to pump up the stock with talk around the office, how do you know the company is: BTW, as an option holder only, your brother-in-law's rights to financial information may be limited. Will the company share these details anyway? Or, if he exercised at least one option to become a bona-fide shareholder, I believe he'd have rights to request the financial statements – but company bylaws vary, and different jurisdictions say different things about what can be restricted. Beyond the financial statements, here are some more things to consider: The worst-case risk you'd need to accept is zero liquidity and complete loss: If there's no eventual buy-out or IPO, the shares may (effectively) be worthless. Even if there is a private market, willing buyers may quickly dry up if company fortunes decline. Contrast this to public stock markets, where there's usually an opportunity to witness deterioration, exit at a loss, and preserve some capital. Of course, with great risk may come great reward. Do your own due diligence and convince yourself through a rigorous analysis — not hopes & dreams — that the investment might be worth the risk.