Strategies for a concentrated stock position

A concentrated stock position is when a single company represents a significant fraction of your net worth — often because it's your employer's stock, accumulated through RSUs, options, or an ESPP. Concentration creates returns but also creates risk: a company-specific catastrophe can wipe out a huge piece of your wealth overnight. Diversifying is the rational move, but it often comes with a big tax bill from embedded gains. Here are the ways to thread the needle.

1. Stop adding, start selling on vest

The simplest first step: make sure you're not making the concentration worse. Stop any ESPP contributions, decline optional employer stock purchases, and sell RSUs the moment they vest (they're taxed as income either way, so holding adds no tax advantage). This cuts off the supply side.

2. Gradual, scheduled sales

Instead of selling all at once, sell a fixed percentage or dollar amount on a recurring schedule — quarterly or monthly. This spreads the tax hit across multiple years, smooths out timing risk, and is psychologically easier than one big exit. 10b5-1 plans can formalize this for employees with material non-public information restrictions.

3. Donate appreciated shares

If you give to charity, give appreciated stock instead of cash. You avoid capital gains tax on the appreciation and get a full market-value deduction. Donor-advised funds let you bunch these donations and take advantage in high-income years.

4. Exchange funds

Exchange funds pool concentrated positions from many investors and swap them for diversified fund shares, tax-deferred. Usually require a 7-year lockup and have high minimums ($1M+). Good for very large concentrated positions where the tax savings justify the complexity.

5. Options strategies (advanced)

Covered calls, protective puts, and collars can reduce the downside risk of a concentrated position without triggering a sale. These are complex, have ongoing costs, and often require broker approval. Worth the learning curve only if the position is very large and very appreciated.

The strategies side by side

A worked unwind: $800k of employer stock

Nina, 41, holds $800,000 of employer stock — 55% of her net worth — with a $350,000 cost basis, all long-term. Household income puts her in the 15% capital gains bracket with about $95,000 of headroom before gains would spill into the 20%-plus-NIIT zone. Selling everything at once realizes $450,000 of gain: roughly $30,000 of it would be taxed at 15% and the rest at 18.8–23.8%, an estimated $95,000 total tax bill — plus a lost year of ACA or other income-tested benefits if those apply.

Her three-year plan instead: sell $270,000 of the highest-basis lots each year (realizing roughly $150,000 of gain annually, staying mostly inside the 15% rate), redirect every new RSU vest to index funds on vest day, and give her planned $15,000 of annual charitable donations as her lowest-basis shares via a donor-advised fund — erasing the ugliest gains entirely. Estimated total tax: about $68,000, or $27,000 less than the rip-off-the-bandage version, while cutting the position below 15% of net worth by year three. The optimization matters, but notice the order of magnitude: even the WORST tax outcome is smaller than what a 60% single-stock drawdown would do to her net worth. Tax is the tail; concentration risk is the dog.

The 12-month starter plan

1. 1
   Month 1: measure and stop adding

   Compute the position as a percentage of net worth, pull the basis for every lot, and turn off ESPP contributions and dividend reinvestment. Set RSUs to sell at vest.

2. 2
   Month 2: set the target and the calendar

   Pick your destination weight (10–15% max) and a schedule — quarterly sales sized to your capital gains bracket headroom. Put the dates in the calendar; automatic beats deliberate.

3. 3
   Months 3–12: execute mechanically

   Sell highest-basis lots first to minimize gain per dollar diversified, route charitable giving through the lowest-basis lots, and invest proceeds immediately into a diversified portfolio — not cash waiting for a better price.

4. 4
   Every quarter: re-measure

   If the stock rallied, your percentage may have grown despite the sales — increase the pace. The goal is the weight, not the share count.

One more input belongs in every unwind plan: your trading windows. Employees with access to material non-public information can usually only sell during brief open-window periods after earnings — roughly four chances a year, each of which can slam shut on short notice. That's exactly what 10b5-1 plans solve: you file a written schedule during an open window, and the sales execute automatically thereafter, blackout or not. If your unwind depends on manual selling during windows that keep closing, the plan will quietly stall — formalize it instead.

The bottom line

Concentration built your position; only deliberate selling un-builds it. Stop adding, schedule bracket-aware sales, give away the worst lots, and reserve the exotic tools — exchange funds, collars — for positions too large for the simple machinery. The tax bill is real but bounded; the single-stock risk is unbounded, and it compounds every year you wait for a better price that the stock owes nobody.