Updated

New plaintiffs have been added to a revised lawsuit that seeks more than half-billion dollars in damages in last month's Italian cruise ship disaster.

Attorneys said the lawsuit filed Tuesday in Miami-Dade Circuit Court now names 39 individual plaintiffs who were aboard the Costa Concordia when it capsized off the Tuscany coast on Jan. 13. At least 17 people died and 15 remain missing.

The lawsuit names Miami-based Carnival Cruise Lines Inc. and its Costa subsidiary, which has offices in Hollywood, Florida, and Genoa, Italy. The new version seeks $528 million in actual damages. It also seeks $78 million in compensatory damages and $450 million in requested punitive damages.

Many law experts say it will be difficult to win lawsuits in Florida because Costa's cruise tickets require that any legal action be filed in Italy. Passenger lawyers contend Florida is proper because Carnival Corp. and Costa are essentially the same entity.

Other attorneys have announced plans to file lawsuits for passengers in Florida.

Meanwhile, Costa announced Tuesday it will extend its compensation offer for passengers until March 31. The previous deadline had been Feb. 24 for North America and Tuesday for all other countries, said Costa spokesman Buck Banks.

The offer would pay passengers 11,000 euros ($14,485 at current exchange rates) plus reimbursement for cruise ticket costs and extra travel expenses.

"The families of deceased and missing victims and guests who were injured will be covered under a separate proposal based on their individual circumstances," Costa said in a statement, without providing further details.