IBM, AT&T and American Airlines are among the companies lining up against a Texas bill that seeks to restrict bathroom access for transgender people.

The bill is a top priority for some Republicans as state lawmakers reconvene in Austin for a 30-day special session that starts Tuesday.

IBM has taken out full-page ads in major Texas newspapers condemning the proposed legislation and has dispatched nearly 20 top executives to lobby lawmakers, The Texas Tribune reported.

On Monday, the tech giant, which employs more than 10,000 people in Texas, outlined its opposition to the bill in an internal memo sent to thousands of employees around the globe.

“Why Texas? And why now?” wrote Diane Gherson, IBM's senior vice president for human resources. “On July 18, the Texas Legislature will start a 30-day special session, where it is likely some will try to advance a discriminatory 'bathroom bill' similar to the one that passed in North Carolina last year. It is our goal to convince Texas elected officials to abandon these efforts.”

“A bathroom bill like the one in Texas sends a message that it is okay to discriminate against someone just for being who they are,” she added.

More than a dozen major Dallas-based corporations on Monday delivered letters to Republican leaders condemning the bill. Companies lining up against the legislation include American Airlines, AT&T and BNSF Railway.

“This legislation threatens our ability to attract and retain the best talent in Texas, as well as the greatest sporting and cultural attractions in the world,” the companies wrote.

Facebook and Apple previously came out against the measure.