U.S. companies are hoarding so much cash that they're harming shareholder returns and dampening the economic recovery.

That's pretty much the gist of a Wall Street Journal article about the latest report from the Federal Reserve. American companies are sitting on a record $1.85 trillion in cash, which is a lot more than even NBA players carry around. Naturally, that cash is earning piddling interest rates, rather than being used to hire, build, acquire, or start new projects -- all vital factors in a strong economy.

There are solid reasons for U.S. firms to hoard that cash, says the Journal, including fears that Europe's debt problems might lead to more market problems. But eventually, wallets will loosen, and the cash will start to flow again.

Curious about who these cash culprits are, and by extension who might be ready to spend soon, I ran a screen to find out. I was less interested in which companies have the most cash in absolute terms, and more intrigued by the companies with the most net cash (cash minus debt) relative to their size.

I screened for all non-financial U.S. companies with market caps of $500 million or greater, and sorted them by net cash divided by market cap. Here are the top 15:

Company Name

Net cash

Market Cap

Net cash / market cap

Industry

WellCare Health Plans (NYSE: WCG)

$1,027

$1,190

                0.86

Managed health care

Zoran

$400

$513

                0.78

Semiconductors

FormFactor (Nasdaq: FORM)

$433

$555

                0.78

Semiconductor equipment

Celera

$319

$571

                0.56

Biotechnology

IAC/InterActiveCorp.

$1,432

$2,577

                0.56

Internet software and services

EarthLink

$481

$898

                0.54

Internet software and services

Harmonic (Nasdaq: HLIT)

$268

$543

                0.49

Communications equipment

Sonus Networks (Nasdaq: SONS)

$347

$726

                0.48

Communications equipment

Targacept

$282

$594

                0.48

Biotechnology

A123 Systems (Nasdaq: AONE)

$390

$836

                0.47

Electrical components and equipment

Tessera Technologies

$417

$897

                0.47

Semiconductor equipment

Universal American

$507

$1,113

                0.46

Managed health care

Novell

$980

$2,190

                0.45

Systems software

InterDigital (Nasdaq: IDCC)

$482

$1,111

                0.43

Communications equipment

Tellabs

$1,147

$2,655

                0.43

Communications equipment

Data provided by Capital IQ, a division of Standard & Poor's.

WellCare is the king of the cash kings, with a cash hoard that amounts to 86% of its market cap. By comparison, Cisco Systems (Nasdaq: CSCO) has the most total cash of any U.S. non-financial, with $39.1 billion under the mattress. But with more than $15 billion in debt, its net cash position of $23.9 billion represents only 18% of its $130.8 billion market cap.

In thinking about which of these companies may start spending soon on worthwhile projects or acquisitions, it's interesting to note that WellCare and Universal American are in the managed health-care industry. There's a strong insurance component to their businesses, so it seems logical that they'd tend to be more cash-flush than companies in other industries.

More interesting to me are the names in the table related to semiconductors and communications equipment, which would logically be putting more cash to work as the economy recovers. My favorite is FormFactor, which provides crucial testing of chips for semiconductor makers. It's been beaten to a pulp since the economy started sliding, but it's now under new management with more industry experience. FormFactor a "Buy First" stock in our Motley Fool Hidden Gems small-cap service, which believes the stock will benefit greatly as the semiconductor industry continues to improve.

Fool analyst Rex Moore is cash-flush only in the sense of watching his money get flushed away. He owns no companies mentioned in this article. InterDigital is a Motley Fool Stock Advisor recommendation. FormFactor is a Motley Fool Hidden Gems selection. Motley Fool Options has recommended a bull call spread position on FormFactor. The Fool owns shares of FormFactor. The Motley Fool has a disclosure policy.