(Wines&Vines) - Two Oregon wineries announced today, Earth Day, that they had earned B Corp certification, one of the most rigorous sustainability certifications in the world.

Administered by the nonprofit B Lab based in Wayne, Pa., B Corp certifications entail a series of assessments in which companies are scored on how well they meet the organization’s standards for treating employees fairly, respecting the environment and benefiting society in general.

The group also is a leading advocate for states to pass legislation allowing the formation of “benefit corporations,” which are for-profit entities that enjoy the benefits of corporate status yet are legally bound to pursue profit in a sustainable manner.

Winderlea Vineyard and Winery in Dundee, Ore., and Sokol Blosser in Dayton, Ore., join A to Z Wineworks in Newberg, Ore., as the only wineries to earn the certification.

B Lab has certified more than 1,200 companies in 41 countries. Some of the larger firms that have earned B Corp certification include New Belgium Brewing, Ben and Jerry’s, Etsy and Patagonia, according to the group’s website.

In statements announcing their certifications, the owners at Sokol Blosser and Winderlea said the B Corp certification further demonstrates their commitment to operating a sustainable business.