A class action lawsuit alleged that Diamond Pet Foods continued selling dry dog and cat food after internal salmonella tests flagged contamination problems at one of its manufacturing plants, a decision that sickened at least 49 people across 20 states and killed an unknown number of pets. The lawsuit, led by plaintiff Barbara Marciano whose dog Benji died after eating Kirkland Signature Nature’s Domain pet food purchased at a Costco in Westbury, New York, resulted in a $2 million settlement paid by Costco and Diamond Pet Foods. The settlement included a $750,000 fund specifically for consumer purchase claims.
The 2012 Salmonella Infantis outbreak traced back to Diamond’s manufacturing facility in Gaston, South Carolina, triggered one of the largest pet food recalls in recent memory, covering approximately 30,000 tons of product across 17 different brands. What made this case particularly damning was the timeline: Michigan’s Department of Agriculture detected salmonella in a retail bag of Diamond Naturals on April 2, 2012, and notified Diamond the same day, yet the company did not issue its first recall until April 6. During that four-day gap, contaminated products continued shipping to stores.
Table of Contents
- Why Did the Class Action Claim Diamond Pet Foods Kept Selling Products After Salmonella Was Detected?
- What the FDA Found Wrong at Diamond’s Gaston Plant
- The Massive Scope of the Recall and the Brands Affected
- How the Settlement Worked and What Affected Consumers Could Claim
- The Human Health Toll That Diamond’s Recall Notices Downplayed
- Contract Manufacturing and Hidden Supply Chain Risks in Pet Food
- Lessons From the Diamond Case for Future Pet Food Safety Litigation
- Frequently Asked Questions
Why Did the Class Action Claim Diamond Pet Foods Kept Selling Products After Salmonella Was Detected?
The core allegation rested on a well-documented sequence of events. On April 2, 2012, the Michigan Department of Agriculture found Salmonella Infantis in a retail bag of Diamond Naturals Lamb Meal & Rice Dry dog food and immediately notified the company. Three days later, on April 5, the connection between the contaminated pet food and human illness was confirmed, and Diamond was alerted again. Yet the company waited until April 6 to issue its first recall notice, and that notice stated that no illness was connected to the product, despite the company already knowing about confirmed human cases.
The deception did not stop there. When Diamond issued a second recall notice on April 26, 2012, the company changed its wording to say no “dog” illnesses had been reported, a carefully parsed statement that still failed to warn consumers about the dozens of confirmed human salmonella infections. Perhaps most troubling, the FDA later confirmed that product designated for destruction had entered the formal trade, meaning contaminated food earmarked to be thrown away was instead sold to consumers. This pattern of delay, misleading statements, and failed containment formed the backbone of the class action.
What the FDA Found Wrong at Diamond’s Gaston Plant
The FDA conducted a week-long inspection of the Gaston, South Carolina facility and concluded that Diamond did not take “all reasonable precautions” to ensure the safety of its products. Inspectors found equipment failures including conveyor paddles with gouges and cuts that could harbor harmful microorganisms, essentially creating hiding spots where salmonella could survive standard cleaning procedures and recontaminate product batches. Beyond the physical equipment problems, the FDA documented that Diamond lacked adequate testing procedures for both inbound ingredients and outbound finished products. This is a critical distinction.
It was not simply that one batch slipped through; the agency’s findings suggested systemic gaps in quality control. However, it is worth noting that an FDA inspection finding does not automatically prove legal liability. Companies can and do dispute inspection conclusions, and Diamond admitted no wrongdoing as part of the settlement. Still, the inspection report gave plaintiffs powerful evidence that the contamination was not an unforeseeable accident but rather a consequence of inadequate safety infrastructure.
The Massive Scope of the Recall and the Brands Affected
The recall eventually encompassed approximately 30,000 tons of dry dog and cat food spanning 17 brands, many of which consumers would never have associated with Diamond pet Foods. That is because Diamond operates as a contract manufacturer, producing food sold under other companies’ labels. The affected brands included Diamond, Diamond Naturals, Taste of the Wild, Kirkland Signature (Costco’s house brand), Natural Balance, Wellness, Canidae, Chicken Soup for the Pet Lover’s Soul, 4Health (Tractor Supply’s brand), Solid Gold, Country Value, Premium Edge, Professional, and Apex. For consumers, this was a jarring revelation.
A person buying Wellness or Canidae at a premium price point might never have guessed that their pet’s food came from the same South Carolina production line as a budget brand sold at a farm supply store. The breadth of the recall underscored a reality about the pet food industry that most buyers do not consider: a relatively small number of manufacturing facilities produce food for a wide range of brands, and when one plant has a contamination event, the ripple effects can be enormous. Barbara Marciano, the lead plaintiff, experienced this firsthand. She had purchased Kirkland Signature Nature’s Domain, a Costco product, with no way of knowing it was manufactured by Diamond at a facility with documented safety shortcomings.
How the Settlement Worked and What Affected Consumers Could Claim
Costco and Diamond Pet Foods agreed to pay $2 million to resolve the class action, with neither company admitting liability. Of that total, $750,000 was set aside specifically for consumer purchase claims, meaning pet owners who bought recalled products could submit claims for reimbursement. A separate earlier lawsuit against Diamond resulted in a $3.1 million settlement, according to Law360, though the specifics of that agreement covered a different set of claims. The $750,000 cap for purchase claims in the Costco-Diamond settlement highlights a common tradeoff in class action litigation.
Individual payouts in consumer class actions are often modest because the settlement fund gets divided among potentially thousands of claimants. Someone who spent $40 on a bag of recalled pet food was unlikely to receive a large check. On the other hand, pet owners whose animals became seriously ill or died had stronger individual damages claims. Marciano’s case, involving the death of her dog Benji, represented the more severe end of the harm spectrum. Consumers weighing whether to participate in a class action settlement versus pursuing individual litigation should understand this dynamic: class actions provide broad access to compensation but typically at lower per-person amounts, while individual lawsuits can yield larger awards but carry greater risk and cost.
The Human Health Toll That Diamond’s Recall Notices Downplayed
While this case centered on pet food, the human health consequences were significant and arguably under-communicated by Diamond throughout the crisis. The CDC confirmed 49 people across 20 states developed Salmonella Infantis infections linked to Diamond products. At least 22 individuals were confirmed sickened, and in one particularly alarming case, an infant was hospitalized for three days after contracting the bacteria from exposure to contaminated pet food. Salmonella transmission from pet food to humans typically occurs through handling.
A person touches contaminated kibble, fails to wash their hands thoroughly, and then touches their mouth or prepares food. Children and infants are especially vulnerable because they are more likely to put their hands in their mouths and their immune systems are less equipped to fight the infection. The fact that Diamond’s April 6 recall notice stated no illness was connected to the product, when the company had been informed of confirmed human cases the day before, raised serious questions about corporate transparency during a public health event. Consumers relying on that recall notice to assess their risk were making decisions based on incomplete and misleading information.
Contract Manufacturing and Hidden Supply Chain Risks in Pet Food
The Diamond case exposed a structural issue in the pet food industry that persists today. Many premium and boutique pet food brands do not manufacture their own products. They design formulas and outsource production to facilities like Diamond’s Gaston plant. This means a contamination event at a single factory can cascade across brands that otherwise have no operational connection to one another.
For pet owners who choose brands based on reputation and perceived quality, this is an important caveat. Researching where a brand’s food is actually manufactured, which companies are required to disclose if asked, can provide an additional layer of due diligence. After the 2012 outbreak, some of the affected brands switched manufacturers or added their own testing protocols on top of the contract manufacturer’s quality assurance. But the fundamental structure of the industry, with a small number of plants producing food for many labels, means that single-point-of-failure risks remain.
Lessons From the Diamond Case for Future Pet Food Safety Litigation
The Diamond Pet Foods salmonella litigation established several important precedents for how courts and consumers approach pet food safety cases. The timeline evidence, showing that a company was notified of contamination and continued selling product for days before issuing a recall, became a template for demonstrating corporate negligence in subsequent food safety lawsuits.
The FDA’s inspection findings also reinforced the principle that manufacturers bear responsibility for maintaining equipment and testing protocols adequate to catch contamination before products reach consumers. Looking forward, pet food safety regulation continues to evolve under the FDA’s Food Safety Modernization Act, which places greater emphasis on preventive controls rather than reactive recalls. Consumers who suspect their pet has been sickened by a commercial food product should report the issue to the FDA’s Safety Reporting Portal and retain the product packaging, lot numbers, and purchase receipts, as these become critical evidence if litigation follows.
Frequently Asked Questions
What brands were included in the Diamond Pet Foods salmonella recall?
The recall covered 17 brands including Diamond, Diamond Naturals, Taste of the Wild, Kirkland Signature, Natural Balance, Wellness, Canidae, Chicken Soup for the Pet Lover’s Soul, 4Health, Solid Gold, Country Value, Premium Edge, Professional, and Apex. All products were manufactured at Diamond’s Gaston, South Carolina plant.
How much was the Diamond Pet Foods class action settlement worth?
Costco and Diamond Pet Foods agreed to pay $2 million to settle the primary class action, with $750,000 allocated specifically for consumer purchase claims. A separate earlier settlement was reached for $3.1 million according to Law360.
Can humans get salmonella from contaminated pet food?
Yes. The CDC confirmed 49 people across 20 states contracted Salmonella Infantis infections linked to Diamond pet food products. Transmission typically occurs through handling contaminated food and then touching the mouth or preparing food without adequate handwashing. Children and infants are at particularly high risk.
Is there a new Diamond Pet Foods lawsuit in 2025 or 2026?
The primary litigation stems from the 2012 outbreak, with the $2 million settlement finalized around 2014 to 2016. As of this writing, there is no widely reported new lawsuit on this specific topic, though new filings may exist that have not yet received significant coverage.
How do I report a pet food safety issue to the FDA?
You can report suspected pet food contamination through the FDA’s Safety Reporting Portal online. Retain the product packaging, lot numbers, and purchase receipts, as these serve as critical evidence for any potential investigation or litigation.