There’s only so far you can go in trying to patent the ever-popular peanut butter and jelly sandwich.

On Friday, the U.S. Court of Appeals for the Federal Circuit rejected an effort by J.M. Smucker Co. to patent its process for making pocket-size peanut butter and jelly pastries called “Uncrustables.”

Smucker’s peanut butter and jelly pockets are enclosed without a crust using a crimping method that the Orrville, Ohio, company says is one of a kind and should be protected from duplication by federal law.

Patent examiners at the U.S. Patent and Trademark Office disagreed, saying the crimped edges are similar to making ravioli or a pie crust.

Smucker already owns a general patent, which it purchased from Len Kretchman and David Geske, two Fargo, N.D., men who came up with the idea in 1995 and had been baking the products for school children.

The two cases before the appeals court involved two additional patents that Smucker was seeking to expand its original patent by protecting its method.

The company had appealed the initial rejection to the patent office’s Board of Trademark Appeals and Interferences, but that body upheld the decision to reject the patents.

Smucker then took the case to the appeals court, which entered a judgment Friday, without comment, affirming the patent office’s decision.

Brigid Quinn, a spokeswoman for the patent office, said the Smucker case is one of several that seek to test the limits of what federal law has determined can be protected by patents.

“There’s always more than one view on how it can be interpreted,” Quinn said. “They’re intellectual judgments that are crossed with scientific knowledge, and it’s not black and it’s not white. They’re judgment calls.”

The patent office received 376,810 patent applications last year. It usually takes about two and a half years for a patent to be processed. About 65 percent of all patents submitted are approved, Quinn said.

“Very few patents are what one would call a 'pioneer patent,’ meaning that the inventor discovered something very, very new that has never been discovered before,” Quinn said. “Most patents are given to changes to existing technology.”

A spokeswoman from Smucker could not immediately be reached for comment Friday. In a statement released earlier, the company said it had purchased “a unique idea for making an everyday item more convenient” and made a significant investment in a “unique manufacturing process” for making the product.