American companies are increasingly troubled about China’s vigorous enforcement of its six-year-old anti-monopoly law, which appears to be directed more often at foreign companies in recent months, the U.S.-China Business Council said in a report published Wednesday morning. “Eighty-six percent of firms surveyed expressed some level of concern about competition enforcement activities in China,” John Frisbie, the group’s president, said in a statement. “Targeted or not, foreign companies have well-founded concerns about how investigations are conducted and decided. Due process, transparency and the methodology for determining remedies and fines all need improvement.” The report came one day after the American Chamber of Commerce in China released its own report saying that U.S. companies felt increasingly targeted in China. Sixty percent of the respondents said they felt foreign business was less welcome in the country than before, up from 41 percent in late 2013. The increasingly vocal American business complaints raise the profile of the issue ahead of President Barack Obama’s trip to Beijing in November for the annual meeting of Asia Pacific Economic Cooperation forum, which China is hosting this year. It also appears to reflect less confidence that the still relatively young administration of Chinese President Xi Jinping will usher in a new era of Chinese economic openness. Frisbie said it was reasonable to expect that China, the world’s second-largest economy, “will develop into the third leg of the global antitrust regime, along with the United States and the European Union.” But he said the recent uptick in activity has rattled many companies.