It’s well known that many employees at tech companies don’t share in much of the vast wealth created in the sector. Many of the blue-collar workers, such as janitorial and cafeteria staff, aren’t even employed by the company they work at but by contracting agencies. This weekend, four of the biggest agencies, which hire and place security guards at companies including Facebook and Google, agreed to their first-ever labor contract. It covers about 3,000 workers, according to the union-led campaign Stand for Security.

The biggest gain is probably in health benefits, with employers agreeing to cover 75 to 85 percent of premiums by the end of the four-year contract for “the majority” of workers, said the Service Employees International Union in an announcement. The SEIU also said that “many officers” will receive increased vacation days, holidays, and paid sick days.

What about wages? They will increase by $1.20 per hour by January. Workers have been making between about $15 and $20 an hour, depending on local minimum wage rules or standards set by companies like Facebook. Guards commonly work 16-hour shifts to bring in enough money, several of them told the Mercury News, so the pay increase and benefits will help. But the guards are still a long way from the salaries of their engineering and marketing coworkers, living in some of the most expensive cities in the country. (Even working long hours, some guards report being homeless.)

The SEIU and other organizers spent five years pushing for the contract, which was approved on Saturday (and announced on Monday). It includes four of the biggest…