LGBT employees themselves are not surveyed, says Guequierre.
Of 1,737 companies invited to participate, 481 responded and 636 were officially rated.
"Older LGBT workers remember well when coming out of the closet was almost certain to get them fired from their job," says Gueguierre. "And workers over 50 often face discrimination based on their age as well as their sexual orientation or gender identity."
The Civil Rights Act of 1964 — the primary federal antidiscrimination law — makes it illegal to discriminate on the basis of race, sex, national origin or religion but does not specifically address sexual orientation or gender identity.
Less than half of U.S. states have laws protecting gay and transgender employees from discrimination.
Bias is especially an issue for the post-50 LGBT job seeker.
"As an older worker, it's harder to find a job. So it's even more important to be in a work environment where being gay or transgender won't be held against you," says James Fisher, 55, an openly gay senior manager at Booz Allen Hamilton, which made the 2012 list.
One factor in his decision to join Booz Allen Hamilton two years ago is that his partner of 25 years may retire first. "I wanted to make sure I would have the potential to provide health benefits for him," he said. "Knowing he's covered with my benefits when he retires helps me sleep better."
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