Market Structure/Trading mechanics
How to Find Low Float Stocks: A Filing-First Method
How to find low float stocks and know which float you found. Where share counts live in SEC filings, how to build a screen, and the supply a float misses.
The short version
"Low float" means few shares are available to trade, so a given amount of buying or selling moves the price more than it would in a widely held stock. Finding low float stocks is easy: every scanner has a float filter. Finding them and knowing what the number means is the hard part, because there is no official float, every vendor computes its own, and the figure that matters most on a small cap (the shares that can actually hit the tape this week) is the one no vendor publishes.
This guide is a method, not a tool roundup. It covers where the raw share counts are in SEC filings, how to build a screen that states its definition, and the supply a float number leaves out. For a comparison of the scanners themselves and the float each one documents, see best low-float scanners.
Decide which float you mean
Four different numbers get called float. The float vs shares outstanding guide covers each in depth; the short form:
| Number | What it is | Where it comes from |
|---|---|---|
| Shares outstanding | Every issued share | Cover of the latest 10-Q or 10-K |
| Non-affiliate float | Outstanding minus officers, directors and 10% holders | 10-K cover (as a dollar value), proxy ownership table |
| Tradeable float | Non-affiliate float minus restricted and locked-up shares | Your own subtraction; no SEC figure |
| Vendor free float | Each data provider's estimate | The vendor, on its own schedule |
A screen for "float under 10 million" returns different lists depending on which of these the tool uses, and the difference is largest exactly where the filter matters: a company that just closed a private placement can have a public float twice its tradeable float.
Build the screen
Whichever tool you use, a low-float screen has four parts. Write down the setting for each so the list means something tomorrow.
- The float cap, and which float. Under 10 million shares is the common threshold; under 5 million is where the effect of a small float is most pronounced. State the definition the tool uses.
- A price floor. Sub-$1 names carry a Nasdaq bid-price clock and wider Limit Up-Limit Down bands; many brokers restrict them. Choose a floor deliberately rather than inheriting one.
- A liquidity floor. Average daily dollar volume, not share volume. A 3,000,000-share float that trades $40,000 a day can take days to absorb even a modest order.
- A trigger. Relative volume (RVOL) or a gap from the prior close, so the list is "low float stocks that are active today" rather than every thin stock in the market.
Hypothetical Company X: 4,000,000 shares in the vendor's float, $2.50, $900,000 average daily dollar volume, trading five times its usual volume at 9:40 a.m. on a press release. That passes all four. The next section is why passing is where the work starts.
Check the float against the filings
A vendor float is a starting point. Three filings confirm or correct it, and the check takes about ten minutes:
- The 10-Q cover. Shares outstanding as of a stated date. If it is higher than the vendor's shares outstanding, the vendor is stale; the company has issued since.
- The proxy ownership table and recent Form 4s. Officers, directors and 10% holders, with their share counts. Subtracting them from the cover count gives a non-affiliate float you computed yourself.
- Any resale S-1 and its EFFECT notice. Shares registered for resale by private-placement buyers were restricted until the registration went effective (or until the Rule 144 holding period passed, six months for a current SEC filer). After that date they are tradeable float, and the vendor may not have moved them yet.
Also check for a lockup from an IPO or an offering. Locked-up shares are in the non-affiliate float and not in the tradeable one until the date passes; the lockup expirations guide covers where the date is disclosed.
The supply a float number misses
The reason low float is treated as an opportunity is also its trap: a small share count can grow quickly, and the instruments that grow it are not in any float figure.
- Warrants. A 4,000,000-share float beside 6,000,000 warrants at an in-the-money strike is 10,000,000 shares of supply at the warrant overhang level. The warrant table is in the 10-Q equity note.
- Pre-funded warrants. Economically shares already, held off the count to keep a buyer under an ownership cap. Add them to the float.
- Convertible notes. A fixed-price note is a known number of shares; a variable-price note is a number that grows as the price falls.
- An ATM program. New shares can be sold into any active day with no announcement. The ceiling is in a 424B5.
- A reverse split. The quickest way a float gets "low" is a 1-for-20 split. The share count is small until the next financing, and the authorized-share gap the split opened is the reason there is usually a next one.
A low float with none of these behind it and a low float with all of them are different stocks with the same scanner row. The 20-minute dilution check is the fastest way to tell them apart, and how to trade penny stocks covers each instrument.
Short interest needs the same denominator
Short interest as a percentage of float is only meaningful if the float is stated. 1,000,000 shares short is 11% of a 9,000,000-share count, 18% of a 5,500,000-share non-affiliate float and 29% of the 3,500,000-share tradeable float from before the S-1 went effective, all from the same filings. Days to cover has the same problem on the volume side. The short interest guide covers the reporting lag and the borrow data; whichever figure you use, say which float it is on.
How to check a company on Signal8
- The Low Float scanner lists stocks with a float under 10 million shares that are up 5% or more, and the premarket scanner adds gap and RVOL for the active names each morning. The premarket and RVOL guide explains the RVOL baseline.
- Company pages, for example AAPL, show the share count and float data beside the quote and label which figure each is. The Dilution tab, explained in the Dilution tab guide, lists warrants, pre-funded warrants, convertibles and ATM capacity for covered companies, the supply a float number leaves out.
- The Squeeze screener combines float and short interest, which is where stating the float definition matters most.
- A float that is withheld on Signal8 was not measured (for example because two sources disagree on the share basis after a split). It is not a small float, and no other figure should be substituted for it without saying so.
- To see how many times a float changed hands in a session, use the float rotation calculator.
FAQ
What counts as a low float stock?
There is no official threshold. Traders commonly use under 10 million shares, with under 5 million treated as very low. The more important question is which float the number is: shares outstanding, the SEC's non-affiliate float, a tradeable float that removes restricted and locked-up shares, or a vendor's own estimate. Two tools using different definitions can put the same company on opposite sides of a 10 million cutoff.
Where do I find a stock's float in SEC filings?
There is no single float line. The cover of the latest 10-Q or 10-K gives shares outstanding as of a stated date. The 10-K cover gives the market value of shares held by non-affiliates as of the end of the second fiscal quarter. The proxy statement's ownership table lists officers, directors and 10% holders. Subtracting those holders from shares outstanding gives a non-affiliate float; removing locked-up and unregistered shares gives a tradeable float.
Why do scanners show different floats for the same stock?
Because each vendor estimates float with its own method and refresh schedule. Some subtract only insiders, some also remove large institutional holders, some attempt to remove restricted shares, and they update at different times after each 10-Q, Form 4 or offering. The filings are the source all of them start from, so checking the 10-Q cover and the proxy table tells you which vendor figure is closest to current.
Does a low float mean a stock will move more?
A small tradeable supply means a given amount of buying or selling has a larger effect on price, in both directions, which is why low float names appear on both the largest-gainer and largest-loser lists. It does not say which direction, and a float can grow quickly through warrant exercises, conversions, ATM sales or a resale registration going effective. Treat the float as a description of today's supply, not a forecast.
Is float the same as shares outstanding?
No. Shares outstanding counts every issued share, including those held by officers, directors and large holders. Float removes the shares that are not freely available to trade. Public float, as the SEC uses the term, removes affiliates' shares; a tradeable float also removes restricted and locked-up shares. Float is always equal to or smaller than shares outstanding, and on small caps the gap is often large.
Terms in this guide
- Public float
- Public float is the shares held by investors other than a company's officers, directors and controlling holders, or their market value; the SEC uses the dollar figure for form eligibility.
- Non-affiliate float
- Non-affiliate float is the shares, or their market value, held by anyone who is not an affiliate of the company; it is the SEC's float measure and includes restricted shares held by non-affiliates.
- Rule 144
- Rule 144 is the SEC safe harbor that lets holders publicly resell restricted or control securities without registration once conditions such as a holding period are met.
- Lockup agreement
- A lockup agreement is a promise by insiders or investors not to sell or transfer their shares for a set period, commonly 90 to 180 days after an IPO or an offering.
- Pre-funded warrant
- A pre-funded warrant is a warrant sold for almost the full share price up front, leaving a nominal exercise price such as $0.0001, so a buyer can stay under ownership limits until it exercises.
- Warrant overhang
- Warrant overhang is the block of shares that could be created if a company's outstanding warrants are exercised, potential dilution not yet in the shares outstanding figure.
- Relative volume (RVOL)
- Relative volume (RVOL) is a stock's trading volume divided by its typical volume for the same period, so a reading of 3.0 means three times the usual activity.
- Days to cover
- Days to cover is short interest divided by average daily trading volume, a rough estimate of how many days of normal trading it would take short sellers to buy back their shares.
- S-1 resale registration
- An S-1 resale registration registers shares already issued or issuable to named investors so they can sell them publicly; the company itself usually receives no proceeds from those sales.
- Form 10-Q
- A Form 10-Q is the quarterly report a US public company files for each of its first three fiscal quarters, with unaudited financial statements, due 40 or 45 days after quarter end.
- Form 4
- Form 4 is the SEC filing that officers, directors and holders of more than 10% must make within two business days to report a change in their holdings of the company's securities.
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