This bill aims to modify eligibility requirements for amateur sports governing organizations by establishing specific definitions for biological sex. It defines "female" as an individual with the reproductive system that produces eggs for fertilization, and "male" as an individual with the reproductive system that produces sperm for fertilization, clarifying that "sex" means an individual's biological sex. A key provision of the bill amends existing law to prohibit any person whose sex is defined as male from participating in amateur athletic competitions specifically designated for females, women, or girls. This measure is intended to ensure that female-designated sports categories are exclusively for individuals meeting the bill's biological definition of female.