What it means
Managers usually have better information about their company's prospects than shareholders do. This gap is called information asymmetry, which simply means one side knows more than the other.
Signalling theory says managers can narrow the gap by taking actions that are expensive or hard to fake, so that only genuinely strong firms can afford to copy them. The classic example is the dividend.
A firm that raises its dividend commits to paying out more cash each year, which it can only keep up if profits are healthy. Investors therefore treat a dividend rise as good news, and the share price often goes up when it is announced.
Capital structure choices send signals too. A company that borrows heavily is showing confidence that it can meet the repayments, while one that issues new shares is sometimes read as a sign that managers think the shares are fully priced.
Share buybacks signal that managers believe the stock is cheap. Signals only work if they are costly or hard to imitate.
A weak firm that copies a dividend increase may be forced to cut it later, which would damage its reputation and its share price more. That cost is what keeps the signal honest.
Finance teams use the idea when planning announcements. A change to the dividend policy, a large acquisition or a rights issue will be read for hidden messages, so the explanation matters as much as the number.
Poorly handled signals can send the wrong message even when the underlying decision is sound. The approach has critics who point out that markets are noisy and that many things move a share price at once.
A dividend rise during a general market rally, for example, may be wrongly credited with an effect that came from the wider market. This is why researchers measure abnormal returns, which strip out the movement that would have happened anyway.
In practice
Real-world examples.
Example
A mature consumer goods company raises its quarterly dividend by 10% after a strong year. Investors read the move as a sign that management expects stable profits for years. The share price rises as the news reaches the market.
Example
A manufacturing firm announces that it will buy back $50,000,000 of its own shares. The chief executive explains that she believes the stock is undervalued. Analysts view the buyback as a vote of confidence, because management is spending real cash to back its view and cannot easily reverse it.
Example
A technology company with falling sales announces a surprise share issue to raise $200,000,000. Investors worry that managers think the shares are overpriced and sell their holdings. The share price drops by 6% on the day, and the chief executive has to explain that the money is for a specific factory expansion rather than to cover losses.
Formula
Calculation
Abnormal return = actual return - expected return
Value change from the signal = abnormal return x market capitalisation
Suppose a company with a market value of $500,000,000 announces a 20% dividend increase. Based on market movements, investors expected the shares to rise 1% over the announcement window, but they actually rose 4%. The abnormal return is 4% - 1% = 3%. The value added by the signal is 0.03 x 500,000,000 = $15,000,000.Case study
Seen in the real world.
Ashgrove Packaging is an illustrative, fictional listed company that had been quiet about its prospects for two years. Analysts doubted that a new product line would deliver the profits that management had promised.
The finance director proposed a dividend increase of 15%, funded from cash flow rather than from new debt. She explained to the board that the increase would be a costly signal, because cutting the dividend later would harm the company's reputation.
The announcement was followed by a 5% rise in the share price over three days, and analysts raised their profit forecasts. The illustrative lesson is that a signal is believed when the company has put its own money behind it.
Watch out
Common mistakes.
- Assuming any announcement is a signal, when only actions that are costly or hard to copy carry real information.
- Ignoring the timing, so that a dividend change is read as bad news because the explanation was unclear.
- Using the signal to mislead, which damages trust and can lead to legal and reputational trouble.
Questions
People also ask.
What is information asymmetry?
It means that one side of a transaction, usually the managers, knows more about the company than the other side, usually the investors.
Why do dividend cuts hurt share prices?
A cut is read as a sign that management expects weaker profits, and it is hard to disguise, so investors often react strongly.
Does signalling theory always hold?
No, other explanations exist for share price moves, and studies show that the effect of signals varies by company, market and period.
From the founder's library
Take it further with the book.
Build your financial confidence beyond this definition. Shihan's full-length guide, Accounting Fundamentals, takes the same plain-English approach and turns it into a complete, practical playbook for non-finance managers, business owners and students - with chapter-end quiz answers and presentation slides included.
25% off with code MMHQ25, applied at checkout. Priced in USD - checkout may show the equivalent in your local currency.
View the book and save 25%