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strategy May 31, 2026 8 min read

The CANSLIM Method: How William O'Neil Built a Trading Empire

Discover the systematic approach that helped William O'Neil identify winning stocks and build Investor's Business Daily into a financial media powerhouse.

The CANSLIM Method: A Systematic Approach to Stock Selection

William O'Neil developed CANSLIM after studying every winning stock in the market from 1880 to 2009. This wasn't theoretical—it was backed by over a century of real market data.

What is CANSLIM?

CANSLIM is an acronym that represents seven key characteristics of winning stocks:

C - Current Quarterly Earnings


Look for stocks showing strong current quarterly earnings per share growth. O'Neil found that 75% of the biggest winners had earnings growth of at least 70% in the quarter before their major price move.

A - Annual Earnings Growth


The best stocks show a consistent pattern of annual earnings growth over at least 5 years. Look for 25%+ annual growth.

N - New Products, New Management, New Highs


Great stocks often have something "new" driving their business. And contrary to popular belief, you should buy stocks making new highs, not new lows.

S - Supply and Demand


Look for stocks with relatively small supply (fewer shares outstanding) and heavy trading volume on up days.

L - Leader or Laggard


Buy the market leaders in strong industry groups, not the sympathy plays or laggards.

I - Institutional Sponsorship


You want quality institutional ownership—not too much, not too little.

M - Market Direction


Even the best stocks struggle in bear markets. Always trade with the trend.

Why CANSLIM Works

The genius of CANSLIM is that it's not based on theory or gut feelings. It's a rules-based system derived from studying what actually worked historically.

"The whole secret to winning in the stock market is to lose the least amount possible when you're not right." — William O'Neil

Implementing CANSLIM Today

Modern traders can apply CANSLIM using stock screeners, IBD ratings, and technical analysis tools. The key is discipline—following the rules even when it's uncomfortable.

CANSLIMWilliam O'NeilGrowth InvestingStock Screening