The lawsuit was filed on Thursday in United States District Court in New Jersey, a month after a Walmart truck slammed into the back of a luxury van carrying a group that included Mr. Morgan, 45, severely injuring several others and killing James McNair, a comedian known as Jimmy Mack.
The suit says that Walmart was negligent in the ownership and operation of its truck, which was a "substantial contributing factor" in the crash on June 7.
Prosecutors have charged the driver of the truck, Kevin Roper, of Jonesboro, Ga., with vehicular homicide, saying that at the time of the crash he had not slept in more than 24 hours. Mr. Roper has pleaded not guilty.
In their suit, the plaintiffs contend that the company should have known how little sleep its driver was operating on, and that it allowed him to commute an unreasonable distance before starting the shift that brought him to New Jersey.
"As a result of Walmart's gross, reckless, willful, wanton, and intentional conduct, it should be appropriately punished with the imposition of punitive damages," the lawsuit states.
(On Saturday, a publicist for Mr. Morgan, said the comedian had recently left a rehabilitation center, where he had been recovering from injuries that included a broken leg and broken ribs.)
On the morning of June 6, the suit states, Mr. Roper reported to a Walmart distribution center in Smyrna, Del., after traveling there from his home in Georgia - a trip of more than 700 miles that would have taken him more than 11 hours to drive. Walmart, the plaintiffs argue, could have asked him to report to a location closer to his home. The suit claims that Mr. Roper fell asleep at the wheel before the accident. At the time of the crash, Mr. Morgan was returning to New York City with several other comedians after performing a comedy show in Delaware.
Two others hurt in the crash - Mr. Morgan's assistant, Jeffrey Millea, and Ardley Fuqua Jr., a comedian who goes by Ardie - are listed as plaintiffs in the suit.
Walmart released a statement on Saturday saying that the crash was a "terrible tragedy" and that the company hoped the three men would have a full recovery. "We are deeply sorry that one of our trucks was involved," the statement said. "As we've said, we're cooperating fully in the ongoing investigation. We know it will take some time to resolve all of the remaining issues as a result of the accident, but we're committed to doing the right thing for all involved."
The lawsuit seeks a jury trial and punitive and compensatory damages. Mr. Morgan, a former cast member on "Saturday Night Live" and actor on "30 Rock," and the others have not been able to work as a result of the crash and could be left with disabilities that would further prevent them from working, the suit claims. In addition to Walmart Stores, the suit names a subsidiary, Walmart Transportation, as a defendant.
Mr. Millea's wife, Krista Millea, is also listed as a plaintiff in the suit. She was eight months pregnant at the time of the crash and, the suit says, suffered in the absence of her husband.