(CNN) Frozen embryos are not living persons, an appellate court in Ohio affirmed Thursday.

The ruling is the latest development in a case brought by a couple who lost three embryos in a fertility clinic storage tank malfunction last year.

Wendy and Rick Penniman of suburban Cleveland were among the more than 950 families affected by the tank failure in March 2018 at Cleveland's University Hospitals Fertility Clinic. The malfunction caused the temperature to rise, destroying more than 4,000 eggs and embryos.

Their attorney, Bruce Taubman, sought a legal declaration that life begins at conception, which would allow the embryos to be treated as persons and former patients, not property, under Ohio law.

"If the legal status of embryos is not declared to be that of a person, the Plaintiffs will not be able to bring a cause of action for wrongful death and will not be able to seek relief for the mental anguish incurred by the Plaintiffs as surviving parents," Taubman wrote in his original complaint last year.

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