Last year, a company called Lodsys began contacting developers of iPhone and iPad apps utilizing in-app purchases, alleging that their use of in-app purchases, functionality provided for by Apple, violated a patent it owned.

Patent trolling has become so common that this wouldn’t be surprising, but there was a wrinkle in Lodsys’ case: Apple itself was already a licensee of the Lodsys patent in question.

Apple believed that its license covered developers building iOS apps, but Lodsys begged to differ. Enter attorneys stage left.

In June 2011, Apple filed a motion requesting that it be allowed to intervene in a lawsuit Lodsys filed against a number of developers who refused (or were unable) to pay up. Lodsys, for obvious reasons, urged the court not to allow Apple to get involved.

After a long wait, the judge in the case has partially granted Apple’s request, issuing an ruling on Apple’s motion that states in part, “Apple is permitted to intervene in this suit, but such intervention is limited to the issues of patent exhaustion and licensing.”

This is obviously good news for the developers doing battle with Lodsys. Many of them are small companies, but big names like Rovio find themselves in the same boat too. Apple’s ability to argue that these developers are covered by its licensing pact with Lodsys provides an inkling of hope that this matter can be resolved more expeditiously.

“I hope this will help defeat Lodsys” writes FOSS Patents’ Florian Mueller, who at the same time suggests that companies like Apple could do more to protect developers:

I still believe that those large players should do a whole lot more for app developers than what they are doing at this stage (for example, I believe they should give them blanket coverage against litigation costs)…

Given that the patent wars are by almost any measure completely out of control, such protections would be nice. Obviously, they would also expose companies like Apple to significant costs, so we’re unlikely to see them offered. But there’s something meaningful that the Apples of the world can do that doesn’t require a cent: stop feeding the trolls.