One of the largest laboratories on the West Coast for research with monkeys is located in Everett.
The Daily Herald reports the facility currently houses 1,200 monkeys but has room for 4,000. It also houses hundreds of rabbits and dogs and thousands of rodents.
Since moving to the site in 1999, Japanese-owned SNBL USA has kept a low profile, but has drawn complaint from animal rights activists.
Testing on primates is necessary to determine the dosage and safety of drugs, vaccines and therapies for humans.
Company officials say the animals are treated humanely. They are not used for testing consumer products such as cosmetics.
The lab employs 260 workers, including researchers, veterinarians and other staff.