I've found some sources that claim IBM had gotten a patent on making a line thicker using digital means. Does such a patent exist or is this a myth?

Here is one example of the claim from a Forbes article by attorney Gary L. Reback

The chief blue suit orchestrated the presentation of the seven patents IBM claimed were infringed, the most prominent of which was IBM's notorious "fat lines" patent: To turn a thin line on a computer screen into a broad line, you go up and down an equal distance from the ends of the thin line and then connect the four points. You probably learned this technique for turning a line into a rectangle in seventh-grade geometry, and, doubtless, you believe it was devised by Euclid or some such 3,000-year-old thinker. Not according to the examiners of the USPTO, who awarded IBM a patent on the process.

I've never been able to find an actual patent for this on Google.

  • 3
    More egregious are the guys who file generic patent applications and let them linger for years. When they sight a technology (used by someone else) that even vaguely falls in the area of their pending patent, they edit the application to target that technology and the push it forward. The way the Patent Office works, they have "priority" from the day they originally filed their patent, which may be years before the technology was even invented. Oct 15, 2017 at 22:42

1 Answer 1


This answer doesn't require much more than a single link.

US Patent 6930686: Method and apparatus for drawing thick black lines

A graphics system and method with which thick graphic primitives are efficiently drawn by minimizing dependence on drawing algorithms that require appreciable setup time. The method contemplates drawing a thick primitive in which an offset or displacement value is first calculated, based upon the thickness of the graphic primitive. The offset is approximately one half of the thickness of the primitive. Following calculation of the offset value, line drawing parameter values are determined for a line that is parallel to the origin line and displaced from the origin line in a minor axis direction by the displacement or offset value. A loop is then repeated for each grip point in the major axis range of the line. The loop includes an initial step in which a boundary pixel of the thick graphic primitive is drawn using the line drawing algorithm and the line drawing parameter values calculated for the offset line. After the boundary pixel has been drawn, one or more adjacent pixels are drawn using a stepping routine in which the mirior axis coordinate of the selected pixel is either decremented or incremented, depending upon the slope of the line, to write the pixels adjacent the boundary pixel. In this fashion, the present invention draws a thick primitive as a sequence of segments that are parallel to the minor axis of the origin line.

It was assigned to IBM in 1999, and expired in 2009.

  • Hmmm... Reback claims it happened in the late 80s, but this patent wasn't awarded until the late 1990s. Poor memory? It seems unlikely that IBM had TWO such patents.
    – Oddthinking
    Oct 14, 2017 at 4:48
  • 1
    @Nat: Oh, I hope nothing I said suggests for a second that this patent would survive a court battle.
    – Oddthinking
    Oct 14, 2017 at 13:05
  • 2
    Hah naw, just meant that it's plausible that there may've been more than one patent for this sorta thing. And the bit about patents not meaning much is more of a personal compliant; I'm both disappointed in the system and concerned with the trouble that it seems likely to make in the future.
    – Nat
    Oct 14, 2017 at 13:19
  • 1
    Expiration is 20 years from the priority date or June 17, 2019. However it is listed as lapsed so it's likely the fees haven't been paid.
    – Eric S
    Oct 16, 2017 at 1:25
  • 1
    @Acccumulation: Yes, Eric is right. The last line explains "Expired due to failure to pay maintenance fee"
    – Oddthinking
    Oct 16, 2017 at 1:30

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .