Exxon Mobil Corp. on April 13 raised $9.5 billion in new debt, with the largest U.S. oil producer seeking to bolster its finances while debt markets remain open to new deals.

Exxon Mobil paid a lower price to borrow than it did in a similar debt deal almost four weeks ago, a sign of how investor confidence is gradually returning after a rout in energy prices and a stock market collapse fueled by the coronavirus outbreak.

Nevertheless, borrowing costs for Exxon Mobil were still higher than prior to the coronavirus outbreak.

Exxon Mobil raised $9.5 billion by selling five different bonds with a variety of durations ranging from five years to 31 years, up from $9 billion which it had originally planned to raise, indicating robust investor demand.

In an example of how the company's borrowing costs have come down in recent weeks, it priced a 10.5-year bond worth $2 billion at a 185 basis-point premium to U.S. Treasuries with a 2.61% yield. On March 17, Exxon Mobil sold $2 billion in debt with a 10-year duration where the premium to U.S. Treasuries was 240 basis points and the yield was 3.482%.

In August last year, Exxon Mobil raised $1.25 billion through a 10-year bond with a premium to U.S. Treasuries of just 75 basis points and a yield of 2.44%.

The new issue by Exxon Mobil comes as highly rated U.S. companies have been tapping debt markets for cash at a record clip, stocking up on cash due to the uncertainty surrounding the economic impact from coronavirus.

The logic behind Exxon Mobil's deal was to stock up further on cash while the market is still open to issuers of new debt, according to a person familiar with the matter.

Exxon's stock has been hammered this year by the collapse in oil prices, with its share price down 38.7% so far in 2020, a steeper fall than the 14.5% drop in the benchmark S&P 500 Index . In a regulatory filing, Exxon Mobil said it planned to use the proceeds for "general corporate purposes."

Oil prices were mixed on April 13, as the historic production-cut deal signed by major global oil producers was not enough to assuage existing worries about the demand destruction brought on by the coronavirus pandemic.

Other companies to issue new debt on April 13 included U.S. industrial conglomerate General Electric Co., drug store chain Walgreens Boots Alliance Inc. and movie theater operator Cinemark Holdings Inc.