Earlier quoted context omitted.
IANAL, but a 10b5-1 plan (thanks for reminding me of the naming!) is an affirmative defense, that removes insider trading liability if a trade satisfies all of its conditions. Effectively, (1) the plan is created when one does not have material nonpublic information, (2) that it... "- Specified the amount of securities to be purchased or sold, price, and date; - Provided a written formula or algorithm, or computer pr…
The training I went through explicitly laid out this scenario and explicitly classified it as insider trading if material nonpublic information is found that would make those trades desirable to execute. I've never heard of the SEC prosecuting someone for losing money due to insider trading. Again, this probably isn't the case legally. But it was enough for an extremely powerful corporation to deem it as such.
But that's the explicit design of 10b5-1: that it provides coverage if all its requirements are satisfied.
The SEC can charge you for making favorable trades according to a predefined plan, but they're going to have an uphill battle convicting you, if you kept your broker at arms length and didn't alter your plan beyond what was initially communicated.