Relating to the required inclusion of a person's sex on a birth certificate and prohibited change of sex on the birth certificate of certain persons.

SB 406 requires Texas birth certificates to list a person's "biological sex" as male or female based on sex organs, chromosomes, or endogenous profile at birth, as mandated in Health and Safety Code Sections 192.002(c-1) and 192.003(f). It prohibits changing the sex marker on birth certificates except in three specific cases: correcting clerical errors, completing information when biological sex wasn’t initially listed, or for intersex individuals (those with atypical sex characteristics at birth) after medical determination. The bill directly affects parents reporting births, local registrars issuing certificates, and individuals seeking to amend birth records. It does not allow changes to reflect gender identity but permits limited updates for medical clarity or correction of errors.