What Is the Treasury Stock Method and How Does It Affect Diluted EPS?

What Is the Treasury Stock Method: Definition

The treasury stock method (TSM) estimates how many additional shares would enter circulation if all in-the-money options and warrants were exercised. It is required under US GAAP and IFRS when calculating diluted EPS. A guide to equity valuation metrics used by investors covers how EPS fits into the broader set of equity valuation metrics.

The Core Assumption Behind TSM

The treasury method assumes that exercise proceeds are used to buy back shares at the current market price. The difference between shares issued and shares repurchased is the net dilution.

The Treasury Stock Method Formula

The treasury stock method formula is:

Net New Shares = Options Outstanding x (1 - Exercise Price / Market Price)

Or equivalently: shares from exercise minus shares repurchased with the proceeds. Diluted EPS is then:

Diluted EPS = Net Income / (Basic Shares + Net New Shares)

The result is always equal to or lower than basic EPS because net new shares increase the denominator.

In-the-Money vs Out-of-the-Money Options

Only in-the-money options (exercise price below market price) are included. Out-of-the-money options would not be exercised rationally and are excluded from the calculation.

A Worked Example: From Basic EPS to Diluted EPS

Suppose a company has net income of $10 million, 10 million basic shares outstanding, and 1 million stock options with an exercise price of $30. The current market price is $50.

Basic EPS = $10M / 10M = $1.00

Options exercised: 1,000,000 shares issued. Proceeds: 1,000,000 x $30 = $30M. Shares repurchased: $30M / $50 = 600,000. Net new shares: 1,000,000 - 600,000 = 400,000.

Diluted EPS = $10M / (10M + 0.4M) = $0.96

The treasury stock method formula reduced EPS from $1.00 to $0.96, reflecting the dilutive impact of the options. A review of fundamental analysis of company financials helps place this figure in the context of broader financial analysis.

Why TSM Matters for Investors

Diluted EPS is the more conservative measure. A wide gap between basic and diluted EPS signals significant potential dilution from options. Understanding how earnings data flows into stock valuations helps investors see how EPS feeds into valuation models. Traders who follow trading around earnings-related price moves often watch for EPS surprises that result from changes in dilution assumptions.

Conclusion

The treasury stock method calculates the net dilutive effect of in-the-money options on EPS. The treasury method assumes exercise proceeds are used to repurchase shares, and only the net difference increases the share count. The result is diluted EPS, which is always equal to or lower than basic EPS.

Disclaimer: Trading involves significant risk of capital loss. Past performance does not indicate future results. This article is for educational purposes only and should not be treated as financial advice.