Responsibilities of US Residents
Once you receive your EB-1 green card, you will officially be a US tax resident and will be required to file a tax return every year. US taxes can be quite complicated, and so you may want to utilize the help of a tax attorney, accountant, or tax software.
If you are an EB-1 green card holder, you must not be outside of the US for a period of more than 6 months. If you are spending more time outside of the US than within the US and fail to inform immigration that you are giving up your EB-1 green card, immigration will consider this green card abandonment, and you will face potential US re-entry denial in future trips. They also may refuse to give you a visa or green card in the future.
However, there are some exceptions to this rule. For example, if you have to leave the US for educational reasons, you must inform immigration beforehand so they approve your long-term absence, and you must apply for re-entry.
In addition to these tax and residence responsibilities, males from the ages of 18-25 that are green card holders must apply for Selective Service, in the rare case that the government begins a draft for a war.