Moody's Investors Service raised its rating on the debt of LyondellBasell Industries N.V. based on the oil refiner and chemical producer's conservative debt structure.
Moody's upgraded the company's debt to "Ba1," one level below investment grade, from "Ba2."
The ratings agency also placed a "Ba2" rating on $1 billion in new senior unsecured notes that the Dutch company issued Friday. The notes are due in 2021.
Moody's said the debt rating upgrade took into account LyondellBasell's large size and product diversity. The ratings agency also pointed to the company's track record of conservative fiscal stewardship.
Shares of LyondellBasell Industries rose 55 cents, or 1.6 percent, to close at $35.01.