I'm not sure whether I can ask this question here, but since I feel that it is somewhat related to electrical, I am asking here.

  1. I read that the CAN bus was originally developed by Bosch, but they released it at the SAE conference (1986). Similarly, I2C was developed by Philips alone, SPI by Motorola and some others.

My question is: when the CAN bus was released by Bosch at the conference, the other companies started to use this standard in their chips. For example, we have NXP ICs with a CAN interface. In that case, to use the CAN standard in the NXP IC, does NXP have to pay some money to Bosch, or does NXP have to pay some money to the SAE conference? Is it like a membership fee that the companies have to pay to attend the conference and get to know the standards that other companies develop, or are they free to use?

I just want to know how the usage of standards by others work without/with money.


  1. If I google to get some technical standard documents, they seem to be unavailable to me and they are asking me to pay for them. In that case, why should I pay just to learn new things as standards? Why and how do they make/want money just to be able to read standards?
  • \$\begingroup\$ It depends on standard, and it is a general thing for standards in all areas of life, not just related to electronics. Usually a standard contains under what circumstances you can implement it. Some standards might be free to read but may contain patented technology so you can't implement it without license fees. Having a staff to write standards and distributing them costs money so obviously they want money if you want a copy of the standard, no matter what you do with it. \$\endgroup\$
    – Justme
    Jul 25, 2022 at 9:54
  • 1
    \$\begingroup\$ These models go under the general heading of 'coopertition'. One or several companies realise it's in their best interest to get other manufactruers to use their IP, so they make it available at attractive rates. It's all down to how precisely the originating companies choose to licesnse it. \$\endgroup\$
    – Neil_UK
    Jul 25, 2022 at 10:54
  • \$\begingroup\$ Can @Justme please provide an answer on your thoughts on the licensing part of the question? It would be helpful \$\endgroup\$
    – user220456
    Jul 25, 2022 at 11:45
  • \$\begingroup\$ @Neil_UK, Could you please provide an answer to explain your comment? \$\endgroup\$
    – user220456
    Jul 25, 2022 at 12:36

1 Answer 1


Depends, there are all sorts of models.

I2C for example was patented by Phillips and the way it worked is that you were granted a license to use it providing at least one Phillips I2C device was in your design. The patent is well expired now.

I suspect with CAN that Bosch really needed chip manufacturers to pick it up, it is far more useful with an ecosystem around it.

Sometimes standards are free, sometimes it is a membership thing, sometimes you just got to pay up. These things cost money to develop, which is the argument.

  • \$\begingroup\$ Could you please provide an article where the Philips patent and license topic that you mentioned? \$\endgroup\$
    – user220456
    Jul 25, 2022 at 14:00
  • \$\begingroup\$ The patent was US4689740A (Long since expired), Find a copy of the old "THE I2C-BUS SPECIFICATION VERSION 2.1 JANUARY 2000" and look on page 3 for the short statement in section 1.4. Note that Phillips were litigious towards other chip manufacturers and sued at least 5 of them, so using I2C was historically not a problem, but making chips with it did require licensing. \$\endgroup\$
    – Dan Mills
    Jul 25, 2022 at 14:30

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