In a ruling issued last month, a patent examiner rejected Apple's attempt to patent some of the user interface concepts behind the popular digital music player, noting that Microsoft developer John Platt filed for similar claims five months before Apple did.
A Microsoft executive noted on Friday that the company is always open to licensing its technology.
"In general, our policy is to allow others to license our patents so they can use our innovative methods in their products," David Kaefer, Microsoft's director of intellectual property licensing, said in a statement. "Microsoft and Apple have previously licensed their respective patent portfolios to one another and we maintain a good working relationship with Apple."
But in an interview, Kaefer agreed that it may be a bit premature to speculate that Apple will have to send Microsoft a check for each iPod.
Although the decision is considered "final" in patent office terminology, Apple will have the opportunity to try and redefine the scope of its patent so it does not overlap with Microsoft's patent application.
It is also unclear what, if any role, a 1997 agreement between Apple and Microsoft will have. Although the five-year deal has expired, it is theoretically possible that the claims raised in the patent applications might somehow be covered.
Also, Kaefer notes that the two companies are both developing technology in the same areas and both know their way around the patent office.
"We're innovating around sort of parallel paths," Kaefer said. "At least from our perspective, we are both in it together."
Kaefer said he could not say whether Apple and Microsoft are in talks over a broader cross-licensing arrangement. Microsoft has said it is seeking to strike such deals with a broad range of large technology companies.
In a statement, Apple noted that the company "has received many patents for inventions related to iPod, and has many more patents pending."
"The U.S. patent process is often a lengthy one, involving much back and forth with the U.S. patent office," Apple said. "Apple will continue to pursue this patent application, as well as the many others covering iPod innovations."
Apple also stated that it "invented and publicly released the iPod interface before the Microsoft patent application cited by the examiner was filed."
Kaefer said that although Microsoft's patent application does predate Apple's, what could ultimately end up being most relevant is which company first jotted down the basic idea behind the patents.
Attorney Mark Goldstein of the SoCal IP Law Group said that some sort of a licensing deal between the two tech giants might make sense.
"Microsoft and Apple could soon cross paths in court if they don't cross license," he said in an e-mail interview. "As the competition between Apple and Microsoft heats up with Apple's switch to Intel processors, the possibility of suit, rather than a cross license, increases."
Apple's patent office setback was first noted earlier this week by Mac enthusiast site Apple Insider.
