Leaving Cerebras Systems? Plan your 90-day ISO window
Calculator · free · no signup · pre-IPOCerebras Systems is pre-IPO. Left with vested ISOs? Model the 90-day exercise-or-forfeit decision and its AMT cost at any valuation: current 409A or an expected exit price.
Beta · invite-only · AlphaLatitude Inc. · Free Tools
Your grant
Seeded from secondary-market data, as of May 13, 2026
Tax inputs
Grant timeline
Recommended exercise quantity
Exercise all 10,000
With 10%/yr expected growth over the 3-yr hold, every share's expected after-tax gain exceeds its marginal AMT cost. Net value: $382,913 at horizon.
Net after-tax value vs. shares exercised
Each point is the expected after-tax NPV at your hold horizon if you exercise that many shares now and let the rest expire.
Year-by-year tax breakdown
You pay the higher of Regular tax and Tentative AMT per jurisdiction, then subtract Credit recovered. The result is Net tax. Hover any number for the bracket-by-bracket breakdown.
| 1 | 10,000 | |||
| 2 | 0 | |||
| 3 | 0 |
Federal AMT credit
Earned
$312,454
Recovered
$29,764
Remaining
$282,690
The AMT credit only recovers in years where regular tax exceeds AMT — typically a year with no ISO exercise. It carries forward indefinitely (Form 8801) and applies in any future tax year where regular tax exceeds AMT.
Estimates only. Excludes disqualifying dispositions, NSOs, multi-state moves, and AMT preferences other than ISO bargain elements. Long-term capital gains tax assumes a qualifying disposition (ISO held ≥1 yr from exercise and ≥2 yr from grant); state LTCG follows ordinary brackets except where the state grants preferential treatment (HI, ND, SC, WI, AR, NM) or has a dedicated LTCG-only tax (WA). Assumes you are within the $100K ISO limit (any portion of an annual ISO grant whose FMV at grant exceeds $100K is treated as NSO from the start, §422(d)). State AMT figures are 2025 (next-year values published in late 2026). Not financial advice.
QSBS note. If your shares qualify (typically pre-IPO C-corp grants held 5+ years), a federal rule lets you exclude up to $10M of gain on a future sale from federal tax. That single rule shifts exercise-timing math more than AMT does. (This is §1202 “qualified small-business stock”.) Modeled in beta, not here.
You solved the exercise window. The beta plans what comes after it: the new shares, your remaining equity, hedges, and taxes in one multi-year plan.
Request beta access →About Cerebras Systems
Cerebras Systems is a privately held Semiconductors company, incorporated in Delaware and headquartered in Sunnyvale, CA. S-1 filed Apr 1, 2026.
Last reported secondary-market price: $113.5 per share (as of 2026-05-13). Your own 409A may differ.
Expected ticker CBRS.
Equity grants at Cerebras Systems typically include incentive stock options (ISOs) and non-qualified stock options (NSOs).
Cerebras Systems Inc., headquartered in Sunnyvale, California, develops semiconductors, supercomputers, and related software to power artificial intelligence deep-learning applications such as inference engines. Products include its wafer scale engine (WSE)-3 semiconductors, its CS-3 supercomputers, and its "AI inference cloud" and "AI training cloud" APIs, which allow users to access the company's computing power without buying its hardware. The company also builds data centers using its processors and supercomputers to provide cloud computing services directly to clients.
Source: Wikipedia (CC BY-SA 4.0)
Founded in 2016 by Andrew Feldman, Gary Lauterbach, Michael James, Sean Lie, and Jean-Philippe Fricker (the SeaMicro team that sold to AMD in 2012), Cerebras builds wafer-scale AI compute from its Sunnyvale headquarters. The flagship WSE-3 packs 4 trillion transistors onto a single TSMC 5nm wafer, powering CS-3 systems and a high-speed inference cloud. Customers include G42's Condor Galaxy supercomputers and Lockheed Martin. After CFIUS scrutiny of the G42 stake delayed its 2024 S-1, Cerebras refiled and is targeting a Nasdaq debut under CBRS.
Sources: en.wikipedia.org · cerebras.ai · finance.yahoo.com
Equity comp at Cerebras Systems
- Original S-1 filed September 2024 was paused due to CFIUS review of UAE-based G42's investment (G42 accounted for 83% of 2023 revenue and 97% of 2024 hardware sales). CFIUS clearance reportedly obtained in early 2025 but IPO remained on hold; company raised $1.1B at an $8.1B valuation. Refiled S-1 in April 2026 with G42 removed from the investor list, targeting a May 14, 2026 NASDAQ listing under ticker CBRS. Holders face a concentrated tax-withholding event at IPO (about $230M earmarked for RSU settlement obligations) after roughly 18 months of regulatory uncertainty.
Sources: sec.gov · techstartups.com
Researched 2026-05-11.
OptionsAhoy is an independent tool and is not affiliated with, endorsed by, or sponsored by Cerebras Systems.
If you are leaving Cerebras Systems with vested incentive stock options (ISOs), most stock plans give you 90 days from departure to exercise or forfeit them. The calculator works at any valuation: enter your strike and the current 409A fair market value (FMV) or an expected exit price. It computes your window deadline, the alternative minimum tax (AMT) cost of exercising in full, and the partial-exercise share count that maximizes expected after-tax value.
Example: leaving Cerebras Systems with 5,000 vested ISOs at a $34.05 strike, with the last reported price at $113.5, exercising all of them inside the 90-day window puts a $397,250 bargain element into one tax year. Above the 2026 federal AMT exemption ($88,100 single, $137,000 married joint), the 28% AMT rate adds roughly $111,230 on top of regular tax before any state AMT (CA, CO, CT, MN). Exercising fewer shares lowers that bill at the cost of forfeiting the rest; the calculator above finds the count that maximizes expected after-tax value for your exact figures.
All Cerebras Systems tools → · Use the generic Post-Termination ISO Exercise Calculator for any company.
Cerebras Systems equity questions
- I left Cerebras Systems. How long do I have to exercise my ISOs?
- Most stock plans give you 90 days from your departure date to exercise vested incentive stock options (ISOs); unexercised options are forfeited when the window closes. Tax law is slightly wider: ISO treatment requires you to have been an employee within 3 months of exercise (Internal Revenue Code Section 422(a)(2)), so options exercised under an employer-extended window are taxed as non-qualified stock options (NSOs). Check your grant agreement for Cerebras Systems's exact terms. The calculator above computes your deadline from your departure date, the alternative minimum tax (AMT) cost of exercising, and the share count that maximizes after-tax value.
- Does Cerebras Systems grant ISOs, NSOs, or RSUs?
- Equity compensation at Cerebras Systems typically takes the form of incentive stock options (ISOs) and non-qualified stock options (NSOs). Incentive stock options can trigger the alternative minimum tax (AMT) when you exercise.
- Are Cerebras Systems shares eligible for QSBS?
- They might be. Qualified small business stock (QSBS) under Internal Revenue Code Section 1202 can exclude federal tax on much of the gain when shares were acquired at original issuance from a C-corporation while its gross assets were under $50 million, and held at least five years. Whether your Cerebras Systems shares qualify turns on when you acquired them and the company's asset size at that time.
Find another companySemiconductors peers
- Astera Labs (ALAB)PublicOpen →
One piece of the puzzle.
OptionsAhoy plans your Cerebras Systems equity alongside hedging, vesting, and de-concentration, across bullish, neutral, and bearish market scenarios. Free during beta.