Labor unions continued to receive the overwhelming majority of waivers from the president’s health care reform law since the Obama administration tightened application rules last summer.

Documents released in a classic Friday afternoon news dump show that labor unions representing 543,812 workers received waivers from President Barack Obama‘s signature legislation since June 17, 2011.

By contrast, private employers with a total of 69,813 employees, many of whom work for small businesses, were granted waivers.

The Department of Health and Human Services revised the rules governing applications for health reform waivers June 17, 2011, amid a steady stream of controversial news reports, including The Daily Caller’s story that nearly 20 percent of last May’s waivers went to businesses in House Minority Leader Nancy Pelosi’s district in California.

The labor unions receiving waivers include those that are monitored under the 1947 Taft-Hartley Act, and those that are not. The waivers granted since June 17 are valid until 2013, but recipients must make sure their employees understand the “limits of their coverage,” according to HHS documents.

HHS granted waivers on a year-by-year basis under its initial application process, but waivers granted after June 17 are valid for a maximum of two-and-a-half years. (RELATED: Full coverage of the health care law)

By and large, unions backed the health care overhaul, a law from which nearly a half million of their workers are now exempt.

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