"Today LyondellBasell begins writing yet another chapter in our history" as a New York Stock Exchange-listed company," said LyondellBasell Chief Executive Officer Jim Gallogly. "The dedication and commitment of our employees worldwide has enabled us to create a new LyondellBasell, one of the world's premier chemical companies. Having our shares listed on the NYSE provides investors with a more liquid and transparent mechanism to own our stock."LyondellBasell currently has approximately 566 million ordinary shares outstanding, including approximately 343 million Class A ordinary shares and approximately 223 million Class B ordinary shares. The Class A shares previously traded in the over-the-counter market under the symbol LALLF and the Class B shares under LALBF. The combined daily trading volume for the two classes averaged 3.2 million shares since 1 May. LyondellBasell's market capitalisation is approximately USD 15 billion, ranking it among the largest chemical company stocks on the NYSE.LyondellBasell is one of the world's largest plastics, chemical and refining companies. The company manufactures products at 59 sites in 18 countries.