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

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.

Why it matters

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.

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.

Sources

Investor.gov: Fully Diluted Basis · SEC Investor.gov
NVCA Model Certificate of Incorporation · NVCA
PitchBook - MedTech Coverage · PitchBook

Open full page

Select term B to compare.

Why compare MedTech terms side by side?

MedTech terminology is full of pairs that look interchangeable but carry very different regulatory, clinical, and commercial consequences. Picking the wrong framework, pathway, or standard early in a project can add months to a submission, invalidate clinical evidence, or trigger an audit finding. Side-by-side comparison is the fastest way to surface those differences before they become costly mistakes.

Each comparison on this page pulls from the same vendor-neutral, sourced definitions used throughout the MedTech Terms glossary. You see the one-line summary, the formal definition, why it matters in practice, common pitfalls, and the primary sources (FDA guidance, EU MDR/IVDR articles, ISO/IEC standards, MDCG documents, IMDRF principles) that back each entry. That makes the comparison defensible in regulatory strategy memos, design reviews, and submission narratives.

Common comparison patterns

Regulatory pathway choice - 510(k) vs PMA, 510(k) vs De Novo, Abbreviated vs Special 510(k).
Quality systems - QSR vs ISO 13485, QMSR vs QSR.
Software classification - SaMD vs SiMD, Locked vs adaptive AI.
EU frameworks - MDR vs IVDR, CE Mark vs UKCA.
Cybersecurity artifacts - SPDX vs CycloneDX SBOM, CVE vs CVSS.
Post-market actions - Recall vs field action, Removal vs correction.

How to use this tool

Pick term A and term B from the dropdowns, or click a preset above. The URL updates with both slugs so you can bookmark or share the exact comparison with a colleague, a notified body reviewer, or your regulatory consultant. Click Open full page on either side for the complete entry, including FAQs, related terms, and the full citation list. If you are not sure which term to start with, browse the Categories view or the A-Z index.

MedTech Terms is a vendor-neutral community resource sponsored by Blue Goat Cyber. Definitions are written for educational use and are not legal or regulatory advice.