drill bit stock
n. A stock that has a price under one dollar.
Examples
2001
Heard the latest lingo on the Street? It's 'drill bit stocks,' as in stocks trading in the drill-bit range (3/64, 5/16, etc.).
—Andy Serwer, “Loose Change,” Fortune, April 30, 2001
1994 (earliest)
D'Amato sold his Licon stock at a small loss on June 7, 1993, for $ 1.50 a share. Since then, Licon has become what traders call a 'drill bit' stock with offers to buy for about 10 cents a share.
—Jerry Knight, “Stock Firm Seeks to Keep Secret Report Covering D'Amato Trading,” The Washington Post, October 01, 1994
Notes
For those unfamiliar with the hardware section of their local super store, drill bits are identified (mostly) by their diameters, which are measured in fractions of an inch (1/4, 3/8, 7/16, and so on). Stock prices used to have a fractional component, which was generally quoted in sixteenths of a dollar (called a teenie by stock market insiders). So if a stock price is less than a dollar, it would be quoted using just the sixteenths fraction, which might sound like a drill bit diameter.

However, there are no major stock markets that trade in sixteenths nowadays. (The New York Stock Exchange finally converted to the decimal system on January 29, 2001.) So I thought it was a bit peculiar to see a supposedly new term that invokes the old system. After a bit of digging, I found that this term wasn't brand new, but it's not ancient, either.
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