Corporate credit markets were busy last week with more than $23 billion of new debt issued. Eleven companies swiped their credit cards for a billion dollars or more. Who's doing all that borrowing and what are they doing with the money? Here are some of the stories.

Ecolab (NYSE: ECL) topped the borrowing brigade with four issues totaling $3.75 billion. Maturities ranged from three to 30 years with coupon rates from 2.375% to 5.5%. Most of the money will go to repay borrowing and costs related to its deal for Nalco. Share repurchases get $500 million of the new cash. This new debt significantly adds to Ecolab's debt burden, and I think shareholders would be better off skipping the share buy to hold the debt level down.

Gilead Sciences (Nasdaq: GILD) was a close second with four issues totaling $3.7 billion. Maturities range from three to 30 years with coupon rates from 2.4% to 5.65%. Gilead's new cash goes toward its Pharmasset (Nasdaq: VRUS) acquisition. Arbitrageurs may want to take a look at this one. Pharmasset closed Friday at $129 and the cash deal is priced at $137.

Next in line for big bucks was Hewlett-Packard (NYSE: HPQ) with $3 billion in maturities from three to 10 years at 2.625% to 4.65%. The money will be used "for general corporate purposes, which may include the repayment of our currently outstanding commercial paper." For $3 billion one would think Hewlett-Packard could give a little more detail.

Other companies with a billion or more of new borrowing included Wells Fargo (NYSE: WFC) with $1.5 billion and Duke Energy (NYSE: DUK), Noble Energy, Viacom, and Ford (NYSE: F) with a billion each. Duke's new issue was from its Duke Energy Carolinas subsidiary and Ford's was from Ford Motor Credit. Lower rates will save Duke at least $15 million per year in interest compared to debt it's refinancing. Noble is using about half the money to pay off commercial paper. Viacom is paying off commercial paper and mentions a share buyback. Ford Credit's money "will be available for the purchase of receivables, for loans and for use in connection with the retirement of debt." Wells Fargo doesn't give any details beyond general corporate purposes.

An interesting common thread is paying down commercial paper. Hewlett-Packard, Noble, and Viacom are all using new debt to pay off lower rate commercial paper. That looks a lot like CFOs protecting their companies against the risk of rising short-term rates.

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