WILLIAM O'NEIL

O'Neil was born in Oklahoma City in 1933 and graduated from Southern Methodist University in 1955. He served in the Air Force, then joined Hayden, Stone & Company as a stockbroker in the early 1960s.

He studied the biggest winning stocks from 1953 onward and found that they shared measurable traits before their big moves. He applied this to Syntex in 1962 — a pharmaceutical stock that went up 200% — and made enough to buy a seat on the NYSE at age 30, one of the youngest people to do so at the time.

He founded William O'Neil + Company in 1963, a research firm that built massive proprietary databases of historical stock data. He then did something few traders do: he wrote it all down.

Investor's Business Daily launched in 1984 as a direct challenger to the Wall Street Journal. It never beat the WSJ in circulation but it built a devoted readership of serious traders who relied on the IBD 50 list and the proprietary stock ratings.

He sold IBD in 2016. He died on May 28, 2023, having spent six decades documenting the patterns that make stocks go up.

William O'Neil + Company, Inc. — founded 1963 — provides institutional investors with proprietary stock market databases and research.

It's not a household name but it's used by serious money managers who want data O'Neil spent decades compiling. Investor's Business Daily — founded 1984, sold 2016 — was a national financial newspaper known for the IBD 50 (a list of top-performing growth stocks), the SmartSelect composite rating, and a daily market direction column that told readers whether to be fully invested, partially invested, or in cash.

O'Neil wasn't just a trader. He built an information business around his system.

O'Neil combined what most investors treat as opposites: fundamental analysis and technical analysis. CAN SLIM is the framework.

C is for Current quarterly earnings — strong recent growth, at least 25% up. A is for Annual earnings — three or more years of consistent growth.

N is for New — new products, new management, new price highs. S is for Supply and demand — watch volume to see if institutions are accumulating.

L is for Leader — buy the best stocks in the best industries, not the laggards. I is for Institutional sponsorship — big money has to be buying too.

M is for Market direction — only buy in confirmed uptrends. The system sounds complicated but the essential insight is simple: buy the strongest stocks in the strongest sectors when the broader market is going up.

And sell the moment they fall 7 to 8 percent from your purchase price. No exceptions.

O'Neil's career-defining trade was Syntex in 1962. He identified the pharmaceutical company using his early version of what became CAN SLIM — it had strong earnings growth, a new product (an oral contraceptive), and was showing institutional accumulation.

The stock ran more than 200 percent. He made enough from that one trade to buy a seat on the New York Stock Exchange at age 30.

In the context of his own framework, Syntex was the proof of concept that launched everything.

O'Neil wrote in How to Make Money in Stocks that his worst early mistakes came from holding losers too long — exactly the mistake his 7 to 8 percent rule is designed to prevent. He watched one position fall from $40 to $18 before finally cutting it.

That experience calcified into the stop-loss rule he preached for the rest of his life. He acknowledged openly that the hardest part of the system is following it when you're down and convinced the stock will recover.

The conviction and the stop-loss are in direct conflict, and conviction usually loses you money.

O'Neil believed the market tells you what to do if you're willing to listen. Price and volume are the two data points that matter — everything else is noise.

He thought cheap stocks were cheap for a reason and that buying at 52-week highs was smarter than buying at 52-week lows. His core principle: study the best performers of the past to find the best performers of the future, because the patterns repeat.

He was deeply skeptical of diversification: too many stocks meant too much dilution of your best ideas. He ran concentrated portfolios and expected most of his picks to be small losses, with his returns driven by a handful of big winners.

O'Neil was born in Oklahoma City, Oklahoma, on March 25, 1933, and grew up during the Depression years. He served in the Air Force after college.

He lived and worked in Los Angeles for most of his career and had a family. He was not a public figure in the celebrity sense — no biographical documentary, no famous dinner table stories floating around the internet.

He let his books and his system speak for him. He died on May 28, 2023, at age 90.

O'Neil graduated from Southern Methodist University in Dallas in 1955, where he studied business. He then served in the U.S.

Air Force before entering the brokerage industry. He credited his market education primarily to obsessively studying historical stock data — not his formal schooling.

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