PASADENA, Calif.—After a 10-year legal battle, a federal appellate court has upheld a California law that prohibits opticians and optical stores from selling eyewear and providing eye examinations in the same location. The state’s business codes permits only ophthalmologists and optometrists, considered health care providers, to provide such one-stop shopping for their patients. That law was challenged by three entities representing “dispensing opticians”—Luxottica Group’s (NYSE: LUX) LensCrafters chain, Highmark’s Eye Care Centers of America Inc. and the National Association of Optometrists & Opticians—who said that the law violated the commerce clause of the U.S. Constitution, which gives Congress the sole power to regulate interstate commerce.

In last Wednesday’s decision, the appellate court upheld the law that disallows opticians and optical stores from selling eyewear and providing eye examinations in the same location. These restrictions apply to all opticians and optical stores whether the companies are based in California or elsewhere. In addition, the laws prohibit opticians and optical stores from furnishing, employing or maintaining optometrists and ophthalmologists on their premises, and it prevents them from advertising that glasses and examinations are available at the same location.

In December 2006, U.S. District Judge Lawrence Karlton in Sacramento agreed that the laws were discriminatory and would have allowed opticians and optical chains to offer (and advertise) eye exams in the same space in which eyewear is sold, but a three-judge federal appeals court of the 9th Circuit overturned that decision in 2009. The case was returned to Judge Karlton to decide whether the laws interfered with interstate commerce without being discriminatory. He found they do not, and this decision was confirmed in last week’s unanimous ruling.

“Plaintiffs have not produced evidence that the challenged laws interfere with the flow of eyewear into California,” states the opinion written by Procter Hug Jr., a senior circuit judge from Reno. “Any optician, optometrist or ophthalmologist remains free to import eyewear originating anywhere into California and sell it there.”

Concurring were Circuit Judges Richard A. Paez of Pasadena and Marsha S. Berzon of San Francisco. The next possible step is for those representing the dispensing opticians to petition the U.S. Supreme Court.