In drafting patent various features are decribed by refernce numerals. cannot use brackets, inverted commas, circles or outline. But if a feature 101 has a surface bonded to another feature 102 with a surface it is difficult to indicate the interface bond as all that is shown on the drawings is a single line. My thought is to use the ~ tilde symbol and the >< symbol in combination with the feature referecne numeral. for example in the above example a three leader line to the same interface line would refer to: feature 101 (for example a limb portion) has leader lines to a surface 101~a that is bonded using an adhesive 101>a< that bonds surface 101~a to a second surface 102~a of second limb portion 102b. There is a similar issue when referencing holes in a limb portion of a feature and fixings where a fixing 200 is fixed in a hole 200a and a pin 3000 is retained in a second hole in limb 200b of a feature. A two leader lines to the fixing and the pin could be referring to the hole, the limb portion, the fixing or the pin. Could therefore the ^ symbol be used e.g a limb potion 200b has a first hole 200^a and second threaded hole 200^b where the first hole retains a pin 300 and the second hole engages a fixing bolt 200^1.

The ~,><,and ^ symbols are not brackets, inverted commas, circles or an outline All of which appear in the "BASIC LATIN" keyboard symbols layout in microsoft word.

  • What makes this more clear and readable compared to more conventional notation ?
    – George White
    Commented Jul 27, 2023 at 15:47
  • Do you plan on an expanded, exaggerated schematic view where each thing mentioned can be a distinct line?
    – George White
    Commented Jul 27, 2023 at 15:50
  • According to Euorpean Patent office a feature is indicated by a plain leader line and a surface by an arrowed leader line. Imagine 3 cubes the LH & RH cube have bond surfaces facing the middle cube, the middle one has two surfaces facing L & R an adhesive bonds both LH & RH to middle cube. The bonds and surfaces are a single line on the drawing and I want differentiate what surface is bonded to which surface and what the bond is. An Arrowed and plain leader does differentiate hence the symbols n>x< bond, n~x a surface. Leaders to holes fixings also need to be differentiated e.g. ^x and ^n
    – logikman
    Commented Jul 28, 2023 at 19:36
  • Following on from the above a feature 100A could have two bond surfaces 100A~a and 100A~b. Surface where surface 100A~a is bonded to another feature 101A that has abond surface 101A~a by adhesive 102>a<. The second surface 100A~b of feature 100A is bonded to a third feature 103A and this has 3 bond surfacea 103A~a, 103A~b and 103A~c where only bond surface 103A~b is bonded to second surface 101A~2 by a second adhesive 103>b<. Leader lines with just a number reference would simply point to a line that has no indication of what the line represents.
    – logikman
    Commented Jul 28, 2023 at 19:50
  • @logikman I highly encourage you to post a formal answer. You obviously have a lot of relevant knowledge.
    – Eric S
    Commented Jul 31, 2023 at 2:48

2 Answers 2


Having spoken to a patent examiner in the Uk IPO it appears that the use of "><", "~" and "^" symbols to indicate a bond n><, a surface n~ a hole ^x or fixing ^n would be acceptable in the UK. Where "n" is a numeral and "x" is letter. It does not Necessarily follow that the same would apply in other patent Jurisdictions.


Probably allowed but inventing your own notation convention may not make it easier to read.

  • Thanks George. Perhaps if I have "invented" a new notation I should have patented it ? but now its online here I guess " the Genie is out" so no patentable invention here !!!
    – logikman
    Commented Jul 31, 2023 at 8:02
  • I hope you don’t think a notation system is patentable subject matter.
    – George White
    Commented Jul 31, 2023 at 15:27
  • Not at all !!! I have now spoken to a UK Patent Examiner at the IPO and she is quite relaxed about the use of the >, ~ and ^ symbols in reference numerals. Her view is that examiners have to be pragmatic and providing the symbols used are defined as to their meaning and use in a preamble to the description then they would actually assist understanding what is being referenced in a drawing by interface/boundary lines between features or elements in the patent.
    – logikman
    Commented Aug 1, 2023 at 16:45

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