Amanda Knox is entitled to up to 500,000 euros (NZ$877,000) compensation for her wrongful conviction and imprisonment.
The amount is the maximum that can be paid out by the Italian government for a miscarriage of justice.
But it is not yet known if Knox, and her co-accused Raffaele Sollecito, will apply for the money.
Given the sensitivity of the public's perception of Knox, she may be advised not to appear greedy by making an application.
And it is unlikely she will need the cash. One of her first tasks on returning to the U.S. will be to deal with a mountain of lucrative offers for her story that her PR agent has been fielding from publishers, TV stations and film-makers.
Business mogul Donald Trump has predicted she 'could become a big star and build some dividends' from her imprisonment.
Meredith Kercher's bewildered family vowed to pursue justice yesterday as Amanda Knox flew home with the status of an international star.
Agony etched on their faces, they demanded to know what had 'truly happened' to the 21-year-old British student.
Meredith's dejected mother Arline Kercher, sister Stephanie and brother Lyle described being 'back to square one'.
Lyle said: 'We are left looking at this again, and how a decision that was so certain two years ago has now been so emphatically overturned.'
In stark contrast, beaming American Knox gleefully told friends she felt as if she was 'flying already' as she prepared to leave Rome on a British Airways flight.
She was given VIP treatment when she changed flights at Heathrow, being ushered into the Windsor Suite normally reserved for royalty and foreign dignitaries.
Freed on Monday when her conviction for murdering Meredith was quashed after four years in an Italian jail, she can look forward to making millions from her story.
Shortly after Knox's plane took off, Italian public prosecutor Giuliano Mignini announced his intention to take the case to a third and final appeal, and condemned the decision to free her and her Italian former boyfriend Raffaele Sollecito as a 'massive mistake'.
But even if his application is granted by senior judges, it is highly unlikely that the U.S. would agree to extradite Knox back to Italy.
Exchange student Miss Kercher, from Coulsdon in Surrey, was found semi-naked and with her throat slashed in the Perugia house she shared with Knox in November 2007.
The Kerchers have largely maintained a dignified silence since the murder, while the Knox family have deployed every resource at their disposal, including an expensive PR campaign.
At a press conference in Perugia yesterday, Meredith's family said it was impossible to forgive because no one had ever confessed to the murder.
Knox and Sollecito have been acquitted, and a third defendant, Ivory Coast drug dealer Rudy Guede, remains convicted but has never admitted to the killing.
At Guede's murder trial, he was convicted of committing the crime 'with others'.
Meredith's mother Arline said: 'I'm not interested in Amanda having a show. Either way [Meredith] is not coming home. Their lives have been destroyed. Our lives have been destroyed.'
Lyle Kercher said: 'There is of course a third defendant, Rudy Guede, who is convicted, and at the time I understand the court agreed that he was not acting alone.
'The search goes on to find out what really happened.'
Meredith's sister Stephanie said: 'That's the biggest disappointment, still not knowing that there is someone or there are people out there who know about this. We still don't have any answers.'
Before leaving Italy, 24-year-old Knox said she felt 'no bitterness' towards the country that had jailed her. Her lawyer Carlo Dalla Vedova said: 'Even after all this time, she does not have any resentment or animosity.
'She is a simple girl, always ready to help with great humanity.'
He added: 'Meredith was a friend of Amanda, so we should never forget this. We have to respect the sorrow of the family.'
Knox's friend Giulia Alagna told CBS News they had spoken briefly before she left Italy. She said: 'It was very emotional. She had a healthy, strong and happy voice.
'She just couldn't wait to get on the plane. She told me that even though she wasn't yet on the plane, she felt like she was already flying. She was just very, very happy.'
She said Knox's parents, Curt Knox and Edda Mellas, were 'overwhelmed' to have their daughter back.
Soon after gaining freedom, Knox wrote a letter of thanks to the Secretary General of the Italy-USA Foundation, Corrado Maria Daclon, who lobbied for her release, signing off: 'I love you, Amanda.'
Last night she touched down in Seattle with her family on a British Airways flight. A large blue and green 'Welcome Home' banner was hanging outside her father's house.
Waiting for her were friends and supporters who have waged a relentless PR campaign on her behalf.
Some observers have speculated their positive portrayal of a young woman initially attacked as a cold-hearted party girl influenced the previously hostile Italian media. This in turn may have been the deciding factor in the appeal jury's decision.
The pro-Knox campaign was boosted by a sympathetic U.S. media whose coverage of the case has always largely ignored Meredith Kercher's tragedy, played up the unfairness of Italian justice and played down any evidence that showed Knox in a bad light.
The American media has greeted her release from the 'far-fetched' conviction with the most dramatic language.
Some commentators even compared her treatment to the notorious Salem witch trials of 1692, saying her looks and seductiveness were twisted into a 'villainous cartoon character'.
Celebrations planned for Knox include the 21st birthday party she missed because she was in jail.
Her family have been talking of welcoming her back with a big barbecue, and Knox herself has talked of a desire to simply lie down in a green field.
Meanwhile Sollecito, 27, arrived back home near the southern Italian city of Bari, where his father Francesco said he remained stunned by events. 'He is going around touching things as if he is a child who needs to take back the things of his life,' he said.
Appeals judge Claudio Pratillo Hellman has 90 days to write a report on why he and the jury came to their decision. This will be examined by prosecutors to see on what grounds they can launch their appeal, which is unlikely to be heard until next year.
Knox is not obliged to attend any potential retrial. Lawyer Dalla Vedova said: 'There were other sets of unidentified fingerprints in the murder room. The real culprits are possibly the ones who left the fingerprints.'
Meredith's last resting place is a flower-covered plot in a cemetery not far from the family home. It only bears a small temporary marker but a permanent headstone is expected soon.
- The Daily Mail