Definition
Efficient market hypothesis is the theory that stock prices reflect all available information immediately. You reach for it before you spend — to test whether the problem, the buyer, and the offer are real. Name it clearly, then let the next decision — a hire, a price, a test, or a pass — follow from that meaning.
In the room
How the word shows up in a real conversation.
Two cofounders disagree until they define Efficient market hypothesis. Once they agree it means “Theory that stock prices reflect all available information immediately”, the argument becomes a decision.
Common mistake
Using Efficient market hypothesis as a label instead of a fact. If you cannot point to the evidence — a number, a customer, or a written assumption — you are using the word as jargon.
See also
Founder-market fit
Why this founder is unusually able to win this customer — insight, access, or obsession.
Read definition →
Initial market validation
Process of testing and confirming market demand for a new product or service.
Read definition →
Lean startup
Methodology for developing businesses through validated learning and rapid iteration.
Read definition →
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