Originally Posted by
Polaris OBark
If SRAM was doing this, it probably would be illegal, but at least the motive would be rational (why offer functionality useful to your competitor?). But I can't see any reason (apart from being petty) for Shimano to force them to do it. I also don't understand how they can force this.
I believe in order to make the Di2 integration work with the computer you have to license an encryption key from Shimano to unlock the data and make it readable because they use a special data format different from SRAM or Campagnolo which are standard ANT profile. Like most software licenses it can be revoked based on whatever the original agreement was (i.e. not competing directly with Shimano). Using the key without an agreement would be a theft of IP, and SRAM would probably lose in court.
Edit: Added to say DC Rainmaker has a good summary. It does seem like a dumb move by Shimano.
Note that when you starting using your cycling computer (brand doesn’t matter here) you probably agreed that you did not own any of the software on the device but only had a license to use it and the company retained the right to modify or change it as they see fit. Might be that Shimano will try to shake down the cycle computer companies for more money for this license. Many of these disputes are resolved with someone coughing up more cash.