President Barack Obama has signed his first bill into law.
It abolishes a time limit of 180 days set in a Supreme Court ruling in 2007, on bringing legal action in pay discrimination cases.
The change was prompted by a 10 year legal battle brought by a woman who worked for nearly two decades before discovering she was being paid less than her male colleagues in an Alabama tyre plant.
The bill is named after Lilly Ledbetter who watched with Michelle Obama and Speaker of the House of Representatives Nancy Pelosi, as the president signed the bill in the East Room of the White House.
Mr Obama says it is fitting that the first bill he has signed upholds the principle that everyone is created equal.