Industry trade groups representing producers in several countries have signed on to a letter complaining the PA Wine & Liquor Board is charging what they call “stealth taxes.”

Originally, the board had levied a flat, 30 percent markup on all the products it sold. But the new system adopted in 2016 gave the state Liquor Control Board power to negotiate directly with wholesalers, and then set prices based on those agreements.

The change was pitched as a way to save consumers money, but also pump more money into the state.

But a group of spirits producers from Canada, Australia, New Zealand, Scotland, the United Kingdom, and the European Union say they’re concerned it has made the markups unfair.

The PLCB maintains it has been transparent and open about its pricing, and says it’s having “collaborative” discussions about markups with suppliers.