PARIS, Aug 25 (Reuters) - Pernod Ricard (PERP.PA) shares opened higher on Wednesday after the French spirits group said it would book an additional $163 million in income before tax in its 2021 earnings. The world"s second-biggest spirits group after Diageo (DGE.L) said in a statement it could make a claim on spirits exported from the United States after a U.S. Appeals Court ruled in favour of the National Association of Manufacturers on tax refunding on exported goods. It said the ruling means it can book an additional profit before tax of $163 million of which $33 million is profit from recurring operations. That represents about 1% of organic growth, the company said. Pernod Ricard shares were up 1.02% in early session trading.