The French stock market regulator, The Autorite des Marches Financiers (AMF), announced in a press release that they have added 15 cryptocurrency and crypto-asset investment websites to a blacklist on March 15.

According to the press release, the companies listed ran afoul of the “Sapin II Law”, stating that:

“The investment proposals highlighting the possibility of financial returns or similar economic effects involve intermediation in miscellaneous assets and are now subject to ex ante control by the AMF. Consequently, no offer can be directly marketed in France without prior allocation by the AMF of a registration number.”

The press release then lists 15 offending companies, who continued to advertise and market their services as investment opportunities to the French public, despite new regulations. The blacklist also contains businesses that unlawfully offered investments in commodities like rare earth metals, wine, and diamonds.

The statement reminds consumers that “no advertising materials should make you overlook the fact that high returns always involve high risk.” It further advises consumers to by duly diligent before making an investment, to learn as much as one can about the company or intermediary, and to only invest in a product one understands.

This move by French regulators follows a pattern of suspicious attitudes toward cryptocurrencies from the French government. In December of last year, the Governor of the Bank of France, Francois Villeroy de Galhau, issued a warning on the high risks of investing in Bitcoin, claiming it is a speculative asset, and neither a currency or a digital currency.

In January, France’s Minister of the Economy Bruno Le Maire appointed Jean-Pierre Landau, an open Bitcoin critic, to head a task force to examine cryptocurrency regulation. Landau has called Bitcoin the “tulips of modern times” in reference to Tulip Mania, which swept Europe in the early 17th century.