Oil and gas producers in the US are required by law to seal and cap their wells once they're finished producing. So, how many wells are left uncapped? To find out, a team of researchers focused on oil and gas producers along the coast of the Gulf of Mexico (meaning the states of Alabama, Louisiana, Mississippi, and Texas). That, however, raises a very obvious question: If the wells are legally required to be capped, and the companies can easily afford to cap them, why aren't they? One explanation is that, while the supermajors could eventually end up on the hook due to past ownership, they are not the present owners, and those present owners may not be as well-positioned financially to pay for decommissioning