What it means
Economists use the word firm for any entity that buys inputs, transforms them and sells outputs. That covers a sole trader mowing lawns, a partnership of forty architects and a listed multinational, because all three do the same fundamental thing.
The classic question in economics is why firms exist at all, given that everything they do could in principle be arranged through individual contracts in a market. The usual answer is transaction costs: it is cheaper and faster to employ people and coordinate them internally than to negotiate a fresh contract for every task.
That reasoning also sets the natural size of a firm. A business grows by bringing activities inside its boundary until the cost of coordinating one more activity internally exceeds the cost of simply buying it from the market, which is the calculation behind every outsourcing decision.
In common business usage the word carries a narrower flavour. Professional services businesses call themselves firms, financial institutions are frequently described as firms, and manufacturers or retailers more often use the word company, though nothing formal separates the two.
Legal form is a separate question from the economic definition. A firm may be a sole proprietorship, a partnership, a limited liability partnership or a corporation, and that choice affects liability, taxation and ownership rather than whether the entity counts as a firm.
In practice
Real-world examples.
Example
A three-partner architecture practice with fourteen staff describes itself as a firm, keeps its work in progress on the balance sheet and distributes profit between partners rather than paying dividends. Its economic behaviour is identical to a small company with three shareholders.
Example
An accountancy firm decides to stop running its own IT support and buy it from a managed service provider. The boundary of the firm has shifted outward for that activity because coordinating it internally cost more than buying it.
Example
A manufacturing firm with $180 million of equity value and $60 million of debt is acquired. The purchase price agreed in the press release refers to enterprise value, so shareholders receive less per share than headline coverage first implied.
Formula
Calculation
There is no formula for the word itself, but the value of a firm as a whole is measured by enterprise value:
Enterprise Value = Market Value of Equity + Total Debt - Cash and Equivalents
Consider a listed engineering business with 12,000,000 shares trading at $15.00, total borrowings of $60,000,000 and cash of $20,000,000.
Market value of equity = 12,000,000 x $15.00 = $180,000,000
Enterprise Value = $180,000,000 + $60,000,000 - $20,000,000 = $220,000,000
The equity is worth $180 million to shareholders, but a buyer taking the whole firm would effectively be paying $220 million for the operating business, because it inherits the debt and gains the cash. If the firm generates $22,000,000 of operating profit, the multiple paid is:
$220,000,000 / $22,000,000 = 10 times operating profit
That distinction between the value of the shares and the value of the firm is one of the most frequently confused points in business valuation.Case study
Seen in the real world.
Ashgrove and Partners is a fictional surveying firm used here only as an illustration. It operated as a traditional partnership with nine partners who shared profit annually and had no share capital, and it wanted to bring in outside investment to fund expansion into three new regions.
The structure made that almost impossible. There were no shares to sell, incoming partners had to buy in from personal savings, and every partner carried unlimited exposure to the actions of the others. The firm's economic activity was healthy, but its legal form limited how it could raise money.
In this illustrative account, Ashgrove converted to a limited liability partnership and later incorporated a service company, which let it raise external capital and separate ownership from day-to-day management. The firm did not change what it did, only the container it did it in.
Watch out
Common mistakes.
- Assuming a firm must be a partnership, when the economic definition covers sole traders, partnerships and corporations alike.
- Confusing the value of a firm with the value of its shares, which ignores debt and cash and misstates what an acquirer really pays.
- Treating firm and company as legally distinct terms in general conversation, when in most contexts they are used interchangeably.
Questions
People also ask.
Is there a legal difference between a firm and a company?
Not in ordinary usage, though some jurisdictions reserve certain naming conventions for particular regulated or professional entity types.
Why do firms exist rather than networks of individual contractors?
Because internal coordination avoids the cost and delay of negotiating a separate contract for every task, an idea known as transaction cost economics.
What determines how large a firm should be?
The point at which managing one more activity internally costs more than buying that activity from an outside supplier.
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