Investors in Europe are dumping ESG funds that lack clear sustainability goals, as the market braces for a major overhaul of environmental, social and governance regulations.

More than €20 billion euros ($21 billion) flowed out of so-called Article 8 funds in the third quarter, bringing exits over the last six months to €42 billion, according to a report by Morningstar on Wednesday. The researcher said the exodus disproportionately affected funds with weak sustainability targets. Meanwhile, funds with tougher ESG investment requirements saw inflows of €1.4 billion.

Article 8 funds are required to promote environmental and social factors, leading to a range of strategies from simple exclusions to active engagement. The European Commission is looking into reworking rules that guide such allocations, known as Sustainable Finance Disclosure Regulation.

“Two and a half years after SFDR came into force, and despite the challenging macroeconomic and regulatory environment, asset managers continued to shape their offerings around the regulation, upgrade funds to Article 8, and commit to more sustainable investments,” Hortense Bioy, global director of sustainability research at Morningstar, said in the report. “With the new SFDR consultation launched by the EC in September, we can expect more uncertainty ahead.”