Bret Thorn reports at  Nation’s Restaurant News that the Humane Society of the United States, or HSUS, has purchased shares in Steak ’n Shake Co. and Jack in the Box Inc. in an attempt to influence their purchasing decisions with regard to chicken, eggs and pork, the political lobbying group said.

The HSUS holds a stake in 38 food-related companies, and works to pressure companies to change procedures or purchasing decisions related to animal welfare.

“The HSUS intends to use its stockholder position to move the company toward moving away from eggs from caged hens, pork from crated pigs and poultry from producers that use a particularly cruel but standard method of slaughter…” it said in a statement this week announcing its purchase in Steak ’n Shake stock.

“Steak ’n Shake’s complete lack of meaningful movement on animal welfare puts the company at odds with its competition and public opposition to farm animal abuse,” said Matthew Prescott, corporate outreach director for the group’s factory farming campaign.

In announcing its purchase of Jack in the Box shares, HSUS said it would encourage that company to “influence its poultry suppliers to switch from the current slaughter system … to controlled-atmosphere killing (CAK), which has been shown to greatly improve animal welfare.”

Indianapolis-based Steak ’n Shake, which franchises or operates 485 family-dining restaurants, did not return phone calls at press time.

A spokesman for San Diego-based Jack in the Box, which operates or franchises 2,200 quick-service restaurants and also owns the 500-unit Qdoba fast-casual burrito chain, said the company had no comment about the stock purchase.

Richard Lobb, spokesman for the National Chicken Council, which represents chicken producers and processors, said the HSUS “is basically PETA with a nice suit,” referring to the animal rights group People for the Ethical Treatment of Animals.

Read more: Nation’s Restaurant News