Meta will pay up to $18 billion to resolve claims by U.S. states that ​Facebook and Instagram are designed ​to keep young users hooked, ending one of the highest-profile tests ​of allegations that social media companies harm children.The agreement, reached during a California federal trial, includes monetary payments and nationwide changes to Meta's services for teenage users.WHAT WERE THE ALLEGATIONS?States alleged Meta used its ‌social media ⁠platforms to ⁠entice and retain young users, misled the public about risks posed to children and violated state consumer-protection ​laws.The lawsuit also alleged Meta violated the Children's Online Privacy Protection Act by collecting, retaining and ​using personal data from children under 13 without proper parental consent.Also Read | Meta reaches $16.68 bn settlement over social media harms to childrenWHO BROUGHT THE CASE?The federal trial included consumer-protection claims by California, Colorado, Kentucky and New Jersey. It also included ​COPPA claims brought by 29 states.The settlement extends beyond ⁠the federal ‌trial and includes attorneys general from dozens of states, the District ​of Columbia ​and U.S. territories.WHAT DID META AGREE TO?Meta has agreed to implement ⁠teen safeguards, including a default two-hour daily limit across Facebook ​and Instagram, overnight blocks from midnight to 6 a.m., age-checking ​measures and disabling push notifications during school hours of 8 a.m. to 3 p.m. for teen users.It has guaranteed payment of 70% of the settlement, or roughly $12.7 billion, over a decade.Meta will pay the remaining amount, around $5 billion, only if rivals Snap, TikTok and Alphabet-owned YouTube adopt similar measures, including tighter one-hour-per-app daily limits and wider overnight ‌blocks from 10 p.m. to 7 a.m, and the larger platforms agree to comparable payments to the states.Meta also agreed to hide likes ​and reactions from ​teens by default, including ⁠on their own posts and those of others.The changes will be phased in after the settlement takes effect, with a non-personalized feed due within four months, broader compliance measures ​within six months, and major age-assurance requirements due within one year.Meta has denied wrongdoing and said it has worked to protect children on its platforms.The states set to receive the most from Meta include:State PaymentCalifornia $2.2 billionNew York $1.13 billionTexas $1 billionIllinois $768 millionNew Jersey $752 millionTennessee $739 millionPennsylvania $705 millionNorth $646 millionCarolinaColorado $615 millionKentucky $513 millionVirginia $506 millionMassachusetts $498 millionOhio $457 millionIndiana $410 million