By Aidan Malley

Published: 08:35 AM EST

Apple Inc. may be faced with an uphill battle in its patent litigation with Burst.com after the courts issued a Markman Claim Construction Memorandum that largely sided with its opponent.

Also known as a Markman Hearing and based on a crucial 1996 Supreme Court decision by the same name, a Memorandum is a pre-trial ruling that follows a courthouse debate over the exact meanings found inside a given patent. Its aim is to allow the Court to focus on the core of a patent during trial rather than dwell on its language, which can often bog down disputes with technicalities.

In some situations, however, Markman results have virtually ended trials before they began by almost entirely destroying one side's arguments.

In the case of Burst.com versus Apple, a 48-page Markman decision issued on Tuesday could pose a similar danger to Apple's defense against an April 2006 countersuit by validating many of Burst's concerns over computer media transmission patents, all four of which may cover Apple's iPod and iTunes software.

A Northern District of California judge handling the case has found that about two thirds of Apple's arguments made in the hearing would have created overly narrow definitions of key terms, artificially excluding many of Burst's general but potentially relevant points.

In multiple instances the iPod maker was limiting the patent's relevance to particular hardware or methods when it applies to much more, according to the judge. In one example, the Markman Memorandum notes that Apple's interpretation of a processor for "editing means" is so exacting that it insists only certain Intel, Motorola, and Texas Instruments chips would be valid for the patent, despite their use only as rough examples.

One of the central aspects of the decision was the concept of the "burst time period," a crucial element for Burst's streaming media business and for the patents at hand.  Where Burst said its definition literally applied to the time needed for sending transmission bursts over a network more quickly than in real time, Apple's interpretation of the same term would only have applied burst time to a distinct compression method used to make those transmissions.  This argument would have turned numerous claims "nonsensical" all by itself, the judge said.

Some interpretations nevertheless favored Apple. The California-based firm won preference for some of its own definitions during the courtroom discussion, including the right to exclude auxiliary digital ports as transmitters -- which may affect the iPod's Dock Connector -- as well as ruling that metadata and playlists could not count as editing software.

Still, the mixed reactions by the judge to Apple's legal arguments will create a major obstacles for the consumer electronics firm going forward.

Burst's case is helped by its track record in past lawsuits, as the media streaming firm successfully won a settlement from Microsoft in 2005 over claims that Windows Media Player violated similar patents. The deal netted Burst a $60 million payout in exchange for a non-exclusive license for Microsoft to use Burst technology.