Posts Tagged ‘Magnavox’


 :: Posted by Randel Reiss on 06-02-2013


The Magnavox case law is some of the oldest, and some say first, case law of the video game industry.  As such they address a very core game mechanic which today we simplify by calling “hit-detection.”


  • Document everything you do.
  • Prior patent-licensing can strengthen patent holder legal standing.
  • Modernization of means-plus-function does not invalidate patent.

Document Everything

Some quick background from the ever wonderful Smithsonian.ORG site:

By mid-1967, ping pong videogames were played inside Sanders, patent disclosures were applied for, and hardware was designed. Baer and his associates called the devices they were developing “boxes” and numbered the various versions one through seven. In 1971, Magnavox became Sanders Associates’ first videogame licensee. Between 1972 and 1975, Magnavox produced and sold over 700,000 units of Odyssey, a set of games played on its television receivers. Atari became a licensee in 1976 after the first of many lawsuits won by Sanders in pursuit of patent infringements.

Ralph Baer was an extensive documenting engineer – a lesson for all of us.  The complete text of Ralph Baer’s paper, “TV Game Chronology,” can found here: Download

Prior Licensing

During dispute resolution of Magnavox v. Chicago, Atari founder Nolan Bushnell made a separate out-of-court settlement resulting in a license to use the patent.  This clearly added to the momentum of strengthening the patent against attempts by Activision, Nintendo, and others.

Modernizing Means-plus-function

Ralph Baer’s original work was analog based, although he claimed it was digital.  Notice the analog signal marks below for Baer’s Vertical-stripe generator signified by the saw-tooth lines below:

Vertical-stripe generator

Vertical-stripe generator

The “wow” moment of Baer’s work was when the sync signal from the above vertical-strip signal was combined with some logical AND circuitry against the rectangular dot generator circuitry below, a hit detection of the virtual ball to the virtual wall occurred.

Rectangular dot generator

Rectangular dot generator

Later attempts by Activision to claim the means had no applicability in a microprocessor-driven game failed in the courts.