For a few of the outstanding Covid-19 lawsuits against Princess Cruises, their ability to move forward may be a matter of time.

Specifically, when the passengers aboard the 107,500-gt Grand Princess (built 1998) on a voyage from San Francisco in February contracted the coronavirus.

In seven of the 11 outstanding lawsuits seeking to hold the Carnival Corp brand responsible for exposure to Covid-19, a judge instructed plaintiffs to amend filings to establish that they indeed contracted it during the cruise.

In one, attorneys for Susan Dorety used US Centers for Disease Control and Prevention (CDC) statistics to estimate her husband, Michael Dorety, contracted Covid-19 before an excursion to Hawaii. He later died from the virus.

"Michael Dorety began developing symptoms of Covid-19 a little more than five days after leaving Hawaii," Susan Dorety's amended complaint read, using the CDC's finding that the median time from exposure to the onset of symptoms as five days.

"Specifically, Michael Dorety's symptoms began with a loss of taste, appetite and fatigue."

The ship, she alleged in the lawsuit, was docked in Hawaii when Michael Dorety contracted Covid-19. This would mean that the Death on the High Seas Act would not apply, as Princess had argued.

To date, there have been 29 lawsuits filed against Princess for its handling of the Grand Princess' trip. Each alleges that Princess should have known better than to allow the ship to sail, given an outbreak on the previous voyage.

Many claims dismissed

Many of those lawsuits were thrown out in July, when US District Judge Gary Klausner of the Central District of California agreed with the cruise line that potential exposure did not constitute a claim.

In the remaining lawsuits, the plaintiffs either tested positive, developed symptoms or represent someone who died from Covid-19.

The question in many is when they were exposed to the disease and if Princess can be held responsible for it.

In Michelle and Bruce Grant's lawsuit, Klausner said their complaint did not make clear whether they contracted Covid-19 on the ship, while disembarking at a port of call, during the government-mandated quarantine after disembarkation or elsewhere.

Their amended complaint said they developed symptoms on 9 March and tested positive on 15 March after leaving the ship on 10 March.

A third lawsuit on behalf of 31 passengers saw claims from 14 thrown out as none of the plaintiffs had tested positive or developed symptoms.

The remaining 17 were instructed by Klausner to go back and establish causation.

The Grand Princess was supposed to sail to Hawaii and Mexico from San Francisco, but instead ended up back in the Bay Area after two passengers from the previous voyage had died from Covid-19.

The ship was held for a few days before being allowed to dock in Oakland and passengers allowed to disembark over several days before being put into quarantine.