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    Fully Diluted Shares

    The total share count assuming exercise or conversion of all outstanding options, warrants, convertible securities, and reserved but unissued option pool shares.

    Reviewed by Christian Espinosa, Founder, Blue Goat CyberLast reviewed September 19, 2026

    Definition

    Fully diluted shares represent the total number of shares of common stock that would be outstanding if every outstanding convertible security (preferred stock, convertible notes, SAFEs), option, and warrant were exercised or converted, and every share reserved in the option pool but not yet granted were issued. Fully diluted share count is the denominator used to calculate price per share in a priced round and is central to determining pre-money and post-money valuation, since the same headline pre-money number produces a materially different price per share (and founder dilution) depending on whether the option pool used in the calculation is measured pre-financing or post-financing.
    What the regulation says
    Fully diluted shares is a financing concept, not a MedTech regulatory classification. The SEC's Investor.gov dilution resource provides investor education, not a binding capitalization formula for private financing rounds. There is no universally mandated SEC denominator for pricing every private transaction. Financing documents should specify which preferred shares, convertible notes, SAFEs, options, warrants, and unallocated option-pool shares enter the calculation, together with applicable conversion assumptions. Including an unissued option pool is a negotiated capitalization convention, rather than a requirement that applies automatically whenever the term "fully diluted" appears. Securities-law antifraud requirements nevertheless matter. Section 17(a) of the Securities Act of 1933, enacted May 27, 1933, addresses fraud and material misstatements or misleading omissions in securities offers and sales. Section 10(b) of the Securities Exchange Act of 1934, enacted June 6, 1934, and SEC Rule 10b-5 address fraud in connection with securities purchases or sales. Private-placement exemptions do not eliminate applicable antifraud obligations. For a MedTech financing, capitalization disclosures should therefore clearly explain material dilution assumptions, including whether an option-pool increase occurs before or after financing. NVCA model documents are drafting resources, not legislation or SEC rules.

    What this means in practice

    In MedTech financings, fully diluted counts often include large unallocated option pools reserved for future hires (clinical, regulatory, and quality personnel needed as the company scales toward a pivotal trial or commercial launch), plus warrants issued to venture debt lenders or equipment lessors. Founders should always ask whether a quoted valuation is calculated on a fully diluted basis and, if so, what assumptions were used for the option pool size.

    Examples

    • A company has 8,000,000 founder shares, 1,500,000 granted options, a 1,000,000-share unallocated pool, and a convertible note that will convert into 500,000 shares. Fully diluted shares = 8,000,000 + 1,500,000 + 1,000,000 + 500,000 = 11,000,000, even though only 9,500,000 shares are currently issued and outstanding.
    • At a $30,000,000 pre-money valuation with 15,000,000 fully diluted shares, price per share is $2.00. If the investor instead insists on adding a new 2,000,000-share option pool into the pre-money calculation, fully diluted shares become 17,000,000 and price per share drops to $30,000,000 / 17,000,000 = $1.76, increasing founder dilution even though the pre-money number is unchanged.
    Common pitfalls
    • •Comparing valuations across term sheets without confirming both use the same fully diluted definition; one term sheet may exclude the unallocated option pool while another includes it.
    • •Ignoring warrants issued to a venture debt lender when calculating fully diluted shares, which understates dilution for existing holders.
    • •Assuming outstanding convertible notes convert at face value into a fixed share count; the actual conversion price (and resulting share count) depends on the valuation cap, discount, and round price at conversion.

    Frequently asked questions

    No. Issued and outstanding shares are the shares actually held by stockholders today. Fully diluted shares also include unexercised options, unissued pool shares, warrants, and as-converted convertible securities.

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    Sources

    3 sources

    Every citation below opens the original document. Each is graded against our source-tier hierarchy so you can see what rests on binding law versus commentary.

    Tier 2Regulator guidance and consensus· 1Tier 4Trade press and expert commentary· 2
    Link health: 2 verified 1 unchecked· last checked 2026-06-20
    SEC Investor.gov·1NVCA·1PitchBook·1
    1. 1
      Investor.gov: Fully Diluted Basis
      Tier 2 Unchecked
      SEC Investor.govinvestor.gov
    2. 2
      NVCA Model Certificate of Incorporation
      Tier 4 Verified
      NVCAnvca.org
    3. 3
      PitchBook - MedTech Coverage
      Tier 4 Verified
      PitchBookpitchbook.com

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