During the 1970s and 1980s, the government issued green cards without an expiration date printed on them. People can generally continue to use these cards, but doing so will carry some risks. A green card that says I-151 or Form I-151 in small print on the card is an invalid card and needs to be replaced. People with green cards that have no expiration dates can face problems with entry into the United States, employment, or global entry kiosks.