After years of helping to score major court victories for gay rights, the nation’s largest and oldest LGBT legal organization finds itself battling to hold the line against attacks, including the Trump administration’s latest move to redefine the meaning of “sex” to eliminate transgender.

The Trump administration proposal, according to a draft memo obtained by The New York Times, seeks to define sex as either male or female, to be determined by the genitals with which a person is born. The definition would serve for purposes of applying federal anti-discrimination laws in such areas as education, employment, health care and more.