Apple Inc. and Anheuser-Busch InBev SA may face a tough battle in disputes over European Union demands for back taxes after the bloc’s top court partly backed regulators’ attempt to force Spanish firms to repay millions of euros in tax breaks. In a ruling that could ultimately add impetus to the region’s clampdown on special tax treatment for selected companies, judges at the EU Court of Justice in Luxembourg said a lower tribunal should re-examine a Spanish system that gave tax breaks to companies, including Banco Santander SA, for the acquisition of stakes in foreign firms.