Biggest Small-Cap Gaps on 2026-09-10: Float and Dilution Sourced

Direct answer: On September 10, 2026, four small-caps posted significant intraday gaps: TNON surged +138% intraday (opening gap +72%), SNYR +96% (+48% at the open), IPDN +70% (+44%) and VIOT +38% (+61%). Each move occurred in the context of tight float (between 0.50M and 65.95M shares available) and heavy volume. Public filings show no press release or immediate event for these moves.

Overview of September 10, 2026 Moves

The US small-cap market saw a day marked by four notable intraday moves. TNON (Tenon Medical, Inc.) opened with a +72% gap and reached an intraday peak of +138%, on a float of just 0.50 million shares. Volume traded: 90,663,372 shares. That's a volume-to-float ratio above 180×. Close at $5.3197.

SNYR (Synergy CHC Corp.) followed with a +48% opening gap and an intraday high of +96%. Float: 14.90 million shares. Volume: 130,279,666 shares (ratio ~8.7×). Price: $0.108.

IPDN (Professional Diversity Network, Inc.) opened at +44% and peaked at +70%. Float of 12.83 million shares, volume of 257,444,943 shares (ratio ~20×), price of $0.1414.

VIOT (Viomi Technology Co., Ltd) posted the highest opening gap in percentage terms (+61%) but a more modest intraday move (+38% high). Float of 65.95 million shares, volume of 5,565,397 shares (ratio ~0.08×), price of $1.36.

These figures come from the FloatVerify database, measured on September 10, 2026. No specific catalyst—press release, 8-K filing, regulatory announcement—has been identified in public data available at publication.

Float and Its Impact on Gaps

Float (or free float) is the number of shares actually available for trading. You start with total outstanding shares (visible in 10-Qs or 10-Ks filed with the SEC), then subtract blocks held by insiders and significant institutional positions (Schedule 13G or 13D).

On a gapping small-cap, tight float mechanically amplifies the impact of a given buy volume. When 90 million shares trade on a 0.50 million float (TNON's case), each available share has been traded 180 times during the day, on average. That scarcity pushes price upward: buyers accept higher and higher asks to find sellers.

A wider float (65.95 million for VIOT) absorbs a given volume more easily. 5.5 million shares traded represents less than 9% of the float—a much lower ratio. The move remains significant (+38% intraday high, +61% opening gap), but the mechanics are less strained.

Float is never static. Each share issuance (ATM offering, PIPE placement, warrant exercise, debt conversion) increases the outstanding share count and, often, the float. A company raising capital via an at-the-market offering can see its float double or triple within days. Supply/demand dynamics shift radically. A float measured September 1st can be obsolete by the 10th.

Volume and the SSR Rule

Volume measures the total number of shares traded during the session. It reflects intensity of interest—buyers and sellers combined—without indicating direction. High volume can accompany a rise or a fall. The difference between supply and demand determines direction.

In the cases of TNON, SNYR and IPDN, volumes (90.7M, 130.3M and 257.4M shares) far exceed their floats. Each available share changed hands multiple times—a sign of heavy rotation, typical of sustained gaps.

The SSR rule (Short Sale Restriction, also called the alternative uptick rule) kicks in when a stock drops 10% or more from the prior close. Once triggered, it prohibits short sales at the bid (best buy offer). Shorts can only sell at the ask or higher. This restriction stays active through the end of the next trading day.

The goal: limit selling pressure during sharp declines. SSR does not block short selling entirely, but it slows it down. A short seller must wait for a buyer to lift the price, reducing the effectiveness of rapid bear raids.

For the stocks observed here, no SSR data is provided—we don't know if any were under restriction that day. On such strong upward moves, the SSR rule is rarely the trigger. It applies to declines, not rallies. A major gap can trigger SSR the next day if the stock reverses sharply.

Dilution and Issuance: How Float Evolves

Small-caps, often in growth or financing phases, regularly raise capital by issuing new shares. Common methods:

At-the-market offerings (ATM): the company sells shares directly into the market via a broker, often in small lots. Each sale expands the float progressively.

Private placements (PIPE, Private Investment in Public Equity): the company sells a block of shares to a group of private investors, then files an S-1 or S-3 to register the resale. Once registration is effective, those shares enter the float.

Warrant or option exercise: holders convert their rights into common shares, increasing outstanding share count.

Debt conversion: some convertible bonds can be exchanged for shares, diluting existing shareholders.

Each of these is documented in an 8-K form (material event), an S-1/S-3 prospectus (share registration), or a 424B (final prospectus). Regular reading of these filings lets you track float evolution.

If TNON had a 0.50M float on September 10 and announced a 2 million share ATM on September 12, the float could quintuple within days. A fresh 90 million share volume, on a now-2.50M float, would have far less impact. The volume-to-float ratio would drop from 180× to 36×, still high but less explosive.

Float dating is critical. A number without a date may reflect reality from a month ago, rendered obsolete by recent dilution. FloatVerify displays the measurement date and, when multiple sources (SEC EDGAR, 10-Q, 13G/13D) yield divergent figures, the tool flags this "source split" instead of arbitrarily choosing a single value.

Interpreting a Gap: Mechanics, Not Value Judgment

A gap is the difference between one session's close and the next session's open. An intraday gap measures the spread between the day's low and high. Either way, the percentage reflects the magnitude of the move, not its quality or sustainability.

The gaps observed September 10 (+38% to +138% intraday) illustrate an imbalanced supply/demand dynamic: many buyers, few sellers, or sellers rapidly raising their prices. On tight float, this dynamic amplifies.

A gap does not tell you why the move happened (catalyst, rumor, short covering, retail influx). It does not tell you whether the price is justified by fundamentals (revenue, cash burn, valuation). It does not tell you whether the move will continue, stabilize or reverse.

A gap is a measurement, not a prediction. Many gaps fill—price returns toward pre-gap levels—when demand weakens or dilution expands supply. Others hold if a fundamental catalyst (commercial agreement, regulatory approval, new revenue) justifies a revaluation.

FloatVerify never labels a gap "good" or "bad," "overvalued" or "undervalued." The tool displays float, recent dilution (via SEC filings), cash burn (when available in 10-Qs/10-Ks), and lets the user cross this data with price action to form their own judgment.

Recap

Point	Takeaway
Largest intraday gap	TNON: +138% high, +72% opening gap, 0.50M float, 90.7M volume.
Other notable moves	SNYR +96% (+48% gap, 14.90M float), IPDN +70% (+44% gap, 12.83M float), VIOT +38% (+61% gap, 65.95M float).
Volume-to-float ratio	TNON ~180×, IPDN ~20×, SNYR ~8.7×, VIOT ~0.08×—the higher the ratio, the more mechanically amplified the move.
Float = dated figure	Float changes with each issuance (ATM, PIPE, warrants). A number without a date can be obsolete.
SSR rule	Triggers on a ≥10% decline and restricts shorts to the ask—does not apply to upward gaps but may play the next day if reversal occurs.
Gap ≠ quality judgment	A gap measures a move, not a valuation. It can fill or hold depending on how supply, demand and fundamentals evolve.

FAQ

What were the biggest small-cap gaps on 2026-09-10?

On September 10, 2026, TNON (Tenon Medical) posted the largest move at +138% intraday with a +72% opening gap, followed by SNYR (+96% high, +48% gap), IPDN (+70% high, +44% gap) and VIOT (+38% high, +61% gap). All occurred on stocks with tight float (between 0.50M and 65.95M shares available).

Why does a low float amplify gaps?

The float is the number of shares actually available for trading (calculated by subtracting insider and institutional holdings from total outstanding shares). When heavy volume hits a restricted float, each buy pushes price further because supply is limited. Fewer shares available + sustained demand = larger move.

Where do you find a small-cap's float?

Float is calculated from SEC filings: the 10-K or 10-Q shows outstanding shares, and schedules (13G/13D, Section 16) show blocks held by insiders and funds. The final figure rarely appears as-is in a single document—you cross-reference multiple filings. Float changes with every issuance (ATM, PIPE, warrant exercise) and can shift within days.

What is the SSR rule and when does it apply?

The SSR rule (Short Sale Restriction, also called the alternative uptick rule) kicks in when a stock drops 10% or more from the prior close. Once triggered, it stays active through the end of the next trading day and prohibits short sales at the bid—only sales at the ask or higher are allowed, reducing selling pressure. The rule can slow a decline but does not prevent short selling entirely.

Are high gaps always sustainable?

No. A gap reflects a supply/demand imbalance at a given moment, amplified by tight float. It says nothing about valuation, financial health or future direction. Many gaps fill quickly if demand weakens or dilution (share issuance) expands the float. A gap is a measure of movement, not quality.

Sources

Float, volume and price data come from the FloatVerify internal database, which aggregates and dates information from SEC filings. To verify or dig deeper:

• SEC EDGAR (official filing database): sec.gov/edgar
• Forms 10-Q and 10-K: quarterly and annual reports containing outstanding shares
• Schedule 13G and 13D: institutional ownership disclosures ≥5%
• Section 16 filings (Forms 3, 4, 5): insider transactions
• Regulation SHO (SSR rule): sec.gov
• Forms 8-K, S-1, S-3, 424B: material events, share registrations, final prospectuses

No specific filing URLs are provided here because the observed moves were not accompanied by any established catalyst in public data at publication time.

See the float, sourced and dated, on FloatVerify.

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FloatVerify shows the float, dilution and cash burn of US small-caps, every number sourced and dated—and surfaces divergences between sources ("source split") instead of one falsely certain figure.

Disclaimer: FloatVerify is a data tool, not an investment advisory service. Nothing here is a recommendation to buy or sell. Data, not advice.