Exxon Mobil

ExxonMobil is a notoriously poor place for LGBT people to work if they want equal benefits. Despite being the top Fortune 500 company, the corporation is notorious for failing to provide for its LGBT employees. HRC's Corporate Equality Index rates major U.S. businesses on criteria that determine how well employers maintain safe and equal work environments for their LGBT employees. Here's how ExxonMobil ranked in the 2012 index

ExxonMobil Corp.
Scoring an abysmal -25 on HRC's Corporate Equality Index — the lowest possible score — ExxonMobil claims that LGBT protections are "unnecessary" and already covered under other company policy.

No - Prohibits discrimination based on sexual orientation (15 points)
No - Prohibits discrimination based on gender identity or expression (15 points)
No - Offers partner health/medical insurance (15 points)
No - Has parity across other "soft" benefits for partners (10 points)
(Half credit for parity across some, but not all benefits)
No - Offers transgender-inclusive health insurance coverage (10 points)
No - Firm-wide organizational competency programs (10 points)
No - Has employer-supported employee resource group OR firm-wide diversity council (10 points)
(Half credit if would support ERG if employees express interest)
No - Positively engages the external LGBT community (15 points)
(Partial credit of 5 points given for less than 3 efforts)
Yes - Employers will have 25 points deducted from their score for a large-scale official or public anti-LGBT blemish on their recent records (-25 points)

Total: -25

Sources:
~  http://www.advocate.com/business/2012/07/19/lgbt-friendly-alternatives-exxonmobil