International Business Machines Corp. (IBM) and steelmaker ArcelorMittal (MT) were among a bevy of corporate borrowers to tap the debt markets Monday, enamored by historically low interest rates and relatively stable market conditions created by a stream of benign economic data.

The day's investment-grade issuance totaled $11.5 billion, which would make Monday the sixth most active day so far this year, according to data provider Dealogic.

IBM raised $1.5 billion in three-year notes, paying 0.30 percentage point more than the yield on comparable U.S. Treasurys. The interest rate was 1%, which Tammy Evans, director of global funding, investments and foreign exchange at IBM, said was a record low for three-year notes. The previous low was 1.75%, set by Praxair last September, Evans said.

"We were being opportunistic because we did see a lot of corporates come to market and price very well," said Evans, director of global funding, investments and foreign exchange at IBM in Armonk, N.Y. "Everyone believed we pushed pricing to the limit, but we were able to meet both sides." ArcelorMittal raised $2.5 billion in a three-part sale that also was priced below initial expectations. One part of the deal, consisting of $1 billion of five-year bonds, was priced at 2.30 percentage points above comparable Treasurys; $1 billion of 10-year bonds was priced at 2.48 over Treasurys; and a $500 million reopening of the company's existing bonds due 2039 was priced at 2.55. Guidance had been set at 2.35, 2.55 and 2.60, respectively.

IBM last came to market in November with 2.10% bonds due May 2013, and on Monday those bonds were bid around 0.15 percentage points over Treasurys, according to data provider MarketAxess.

"Their current three-year issue has been trading extremely rich, meaning they could issue at a fairly aggressive spread," said Russell Brown, portfolio manager at Silvercrest Asset Management.

Also in the market were advertising company Omnicom Group Inc., with $1 billion in 10-year bonds, increased from a $750 million on robust investor demand; Altria Group Inc., with $200 million more of the 4.125% bonds due September 2015 it first issued in June; and Citigroup and Credit Suisse, for $3 billion and $2 billion, respectively. Expedia Inc. offered $750 million of 10-year bonds and Newell Rubbermaid offered $550 million with a similar maturity.

In its deal, Citigroup found investors so enthusiastic that it added some five-year bonds to an existing offering of 10-year bonds to meet demand for shorter-dated paper. Both priced at 2.55 percentage points over Treasurys. The five-year part of the deal was a reopening of the firm's existing 4.75% issue due May 2015.

"At the right price, Citi was happy to do it," said Jonathan Duensing, head of corporate credit at Smith Breeden Associates, an asset-management firm based in Durham, N.C.

Unlike bonds from non-financial corporations, which in some cases sold below expectations, Citigroup's 10-year bonds priced where forecast, at 2.55 percentage points above Treasurys.

Duensing said that difference highlights the split that still exists in the market between financial institutions, still tainted by bankruptcies and bailouts, and other borrowers.

"I believe there has been a book of issuers who have been wanting to come to market and been picking their spots," Duensing said. "Away from financials, you're tending to get very good sponsors for infrequent issuers."

Excluding medium-term note issuance, Credit Suisse this year has tapped the market four times for $6.5 billion with high-grade bonds and Citigroup twice for $4.8 billion.

Omnicom's 4.45% bonds priced at a discount for a yield of 4.493%, or a spread of 155 basis points over Treasurys; while Altria's bonds priced at 1.47 percentage points over Treasurys, inside where they were offered at 1.60 percentage points, for a yield of 3.083%. Meanwhile, Newell Rubbermaid's 4.7% bonds priced at a discount to yield 4.705%, or a premium of 1.75 percentage points over Treasurys, while Expedia's 5.95% bonds also priced at a discount to yield 5.964%, or a spread of 3 percentage points.

Investors said the best pricing is being obtained by issuers that rarely come to market. Before Altria's 4.125%, $800 million issue in June, it last came to market in February 2009 for $4.23 billion. Newell Rubbermaid's most recent U.S. investment-grade bond was in March 2009 for $300 million, and Expedia's most recent U.S. high-grade bond was in August 2006 for $500 million.

By comparison, the financials keep coming back. Last week was the most active week for U.S. marketed financial institutions issuance, across high-grade and high yield, since mid March. So far this week, financials U.S. issuance is at $6.72 billion.

-By Katy Burne, Dow Jones Newswires; 212-416-3084; katy.burne@dowjones.com