Buying options is completely orthogonal to insider trading. Options contracts are not allowed because it's written in the employee contract and that's because c

Buying options is completely orthogonal to insider trading. Options contracts are not allowed because it's written in the employee contract and that's because companies don't want you to be engaging in stock activity that goes against the company. But not because it's illegal. If you're no longer an employee, you can buy whatever you want. If you have MNPI you can't buy or sell anything, including stocks or options, even if you don't work for the company.