A gourmet popcorn company is suing a former executive that it accuses of stealing corporate data, including secret recipes.

CHICAGO — Garrett Popcorn Shops says it guards its recipes so closely that only three employees have access to the information, by verifying their identity via thumbprint.

The company, whose formal name is Caramel Crisp, filed a federal lawsuit last week against one of those three people who it says was fired in early March, alleging that more than 5,000 files were wrongfully downloaded in the days before the termination, putting its secret recipes at risk.

The former employee, Aisha Putnam, served as the director of research and development for about four years at the Chicago gourmet popcorn chain, according to the lawsuit, filed in U.S. District Court for the Northern District of Illinois. In that role, she had access to some of Garrett’s highly confidential trade secrets, along with the CEO and a vice president, the lawsuit states.

The release of Garrett’s secret recipes, formulas and other trade secrets “would be severely detrimental” to its business and “cause irreparable harm,” the lawsuit states.

“Once it has been shared, there is no way to ‘undo’ the disclosure,” the complaint says.

Putnam did not respond to a request for comment.

Though Putnam signed confidentiality agreements throughout her tenure, she found out that she would be fired and began to download Garrett’s secret information, according to the lawsuit. She allegedly saved the information to a USB drive and sent it to her personal email account, the lawsuit states.

The information Putnam sent herself included pricing, product processes, distribution agreements, supplier information, market research and more, according to the suit.

When Putnam was fired, the lawsuit alleges, she took with her a USB drive to which she had copied more than 5,400 files, containing the “overwhelmingly vast amount of data” that had ever been stored on her work computer or provided to her.

After Putnam left the company, she signed a document saying she deleted all the information in her possession protected by one of the confidentiality agreements, but she refused a forensic review of her electronic devices, according to the lawsuit. Garrett “reasonably doubts that Putnam is now suddenly telling the truth about her actions,” the lawsuit states.

The company said in the lawsuit that it will continue to suffer harm until the court enters a restraining order against Putnam that stops her from using, possessing or benefiting from the trade secrets.

Garrett and attorneys representing Putnam and Garrett did not immediately respond to requests for comment.