You opened the email or saw the alert, and the headline read something like "acquired for up to $4 billion." Your biotech. The one whose stock options and restricted shares you've been holding, waiting for exactly this kind of day. And the first honest question in your head is the right one. What does this actually mean for my equity, and how much of that number is really mine?
Here's the short version. A big pharma buyer is, on paper, the liquidity event everyone hoped for. But the headline number is rarely the number you keep, and the structure of the deal decides far more than the price does.
What happens to my stock options and RSUs when my biotech is acquired by a big pharma company?
At close, your vested options that are worth more than their exercise price and your owned shares typically convert to cash at the deal price, while your unvested awards either accelerate or carry forward on their vesting schedule, paid in cash or the buyer's stock depending on the deal, as long as you stay — and how each of these is handled is written into your company's stock plan, not the press release.
Three things can happen to your equity and they are not the same thing
It's natural to think of "my equity" as one thing. In an acquisition, it's actually three things, and they go three different directions.
First, the money that becomes cash. Your vested options that are "in the money" — meaning the deal price is higher than your exercise price, the set price you'd pay to buy the share — convert to cash for the difference. Shares you already own convert to cash at the deal price. This is the real, bankable part.
Second, the money that disappears. Options that are "underwater" — where your exercise price is higher than the deal price — are generally cancelled when the deal closes. They may have had value when the stock traded higher, but the deal price is below the cost to exercise them, so they don't receive a payout at close.
Third, the money that's unvested. Awards you haven't earned yet are most often either accelerated at close or carried forward on their vesting schedule — paid in cash or the buyer's stock, depending on the deal — as long as you continue to work for the buyer. How your awards are handled is set by your company's stock plan and the terms of the deal. Reviewing those documents with clients, before close, is a core part of our work.
Two colleagues with similar-looking packages can walk away with very different outcomes based on vesting status alone. Understanding how your awards will be treated before the deal closes leaves the most room to plan, and to catch payout errors while they can still be fixed.
Why "up to $X billion" is a structure and not a payment
That word "up to" is doing a lot of work. Large pharma buyers frequently pay a fixed amount at close, plus additional money tied to future events — a drug hitting a clinical milestone, winning regulatory approval, or reaching a sales target. Sometimes this is packaged as a contingent value right, or CVR, a promise to pay more if specific things happen down the road. Whether any of your own payout is contingent, and how much, depends on the deal.
So "acquired for up to $4 billion" might mean a little over half paid at close, with the rest split into payments that arrive only if a late-stage trial succeeds, the FDA approves, or the product reaches a revenue target after launch.
None of those are guaranteed. Planning around the full announced number means planning around money that depends on outcomes beyond your control, like trial results and regulatory decisions. The right mental model is simple. Treat the upfront cash as real. Treat the milestone payments as a maybe, not a delay.
A cash deal delivers liquidity, and decides the tax timing on your behalf
If your company is private, a cash acquisition may be a better outcome than an IPO. In an IPO, you often face a 180-day lockup — a period after the offering where you're barred from selling — and your shares can fall hard before you're allowed to touch them. A cash deal usually delivers immediate liquidity on the vested, cashed-out portion with no lockup at all. That's a real advantage.
But it compresses what might have been years of gains into a single taxable year. The equity income from your options generally gets taxed as ordinary income — the same rate as your salary — not at the lower long-term capital gains rate. And here's the trap. The company withholds taxes at a flat supplemental rate that frequently falls short of your real combined marginal rate once this windfall stacks on top of your regular pay.
So instead of waiting on liquidity, you're working with a large tax event on a timeline the deal sets. A very large, very sudden taxable event, with a withholding gap between what was taken out and what you actually owe. That gap has to be planned for before the cash lands, not discovered next April.
Is this a clean exit for you or golden handcuffs
Before any retention offer arrives, there's a question worth asking yourself. Is this a clean exit, or golden handcuffs?
Acquirers buy biotechs for the asset, but the asset is often inseparable from the people. The buyer wants to retain the scientific and product talent that makes the molecule worth billions. So for those people, a portion of their value gets restructured — into retention bonuses, or rolled-over awards that revest over additional years at the acquirer.
The lived pattern is that the same transaction is two different events depending on where you sit. For some functions, it's a clean cash exit. For the people the buyer most wants to keep, it's a multi-year arrangement wearing the costume of a payout. Knowing which side you're likely to be on changes how you plan, how you negotiate, and how you think about what comes next.
The real risk is treating the full announced number as money in hand and being surprised by the withholding gap. Sort your equity into the three buckets — cash, contingent, and unvested — build your plan on the cash, and plan for the tax on the cashed-out portion, including the gap between what's withheld and what will be owed, before the proceeds arrive.
Pro-Tip: As soon as a deal is announced, separate your equity into three buckets — what converts to cash at close, what becomes contingent (milestone or CVR payments that may never arrive), and what is unvested and governed by your company's stock plan and the deal terms — and build your plan on the cash bucket, treating the contingent bucket as upside rather than budget. Then, before the proceeds arrive, plan and set aside for the tax on the cashed-out portion this year, with the exact figure confirmed separately, so the withholding gap does not become a forced-sale or estimated-payment problem.
If you'd like to explore whether ongoing financial planning and investment management make sense for your situation, you can schedule an intro call here:
Common Questions
What happens to my vested and unvested equity when my biotech is acquired?
Your vested options that are worth more than their exercise price, along with shares you already own, typically convert to cash at the deal price when the acquisition closes. Vested options that are underwater — where the exercise price is above the deal price — are generally cancelled when the deal closes. Your unvested awards are handled under your company's stock plan and the terms of the deal. They are most often either accelerated at close or carried forward on their vesting schedule — paid in cash or the buyer's stock, depending on the deal — as long as you continue to work for the buyer. How this applies to you is deal-specific, and it's worth having the terms reviewed before close.
What is a CVR and why might I not receive the full announced acquisition price?
A CVR, or contingent value right, is a promise to pay additional money if specific future events occur — a trial succeeding, a drug winning regulatory approval, or a product hitting a sales target — and whether employees receive one depends on the deal. Large pharma buyers often structure deals as an upfront payment plus these contingent payments, which is why the headline reads "up to $X billion." A meaningful slice of that number only pays if those future events actually happen, and many never do. Treat the upfront cash as real money and the contingent portion as upside you don't budget around.
How is the cash from a biotech acquisition taxed, and when do I owe it?
The income from cashing out your options is generally taxed as ordinary income — the same rate as your salary — in the year the deal closes, not at the lower long-term capital gains rate. The issue is timing. Years of potential gains land in a single tax year, and the company typically withholds at a flat supplemental rate that often falls short of your real marginal rate once this stacks on top of your regular pay. That leaves a gap between what was withheld and what you owe, and it comes due when you file. Planning and setting aside for it before the cash arrives keeps that gap from becoming a forced-sale or estimated-payment scramble.
This article was written by Jeremy Bohne, CFP®, CEPA, Principal & Founder of Paceline Wealth Management, a fee-only registered investment adviser (RIA) in Boston. Paceline specializes in equity compensation (RSUs, stock options, M&A, IPOs and concentrated stock) for tech and biotech executives and professionals, and in exit planning for business owners, working with clients in Massachusetts and remotely nationwide.