I am convinced at this point that there is zero chance the sale was pursuant to a plan, however, I don't agree with your reasoning. You may be write that all insider sales are so reported, but since it is not required by law, there is no way to verify that. Further, there is no requirement that the plan be periodic, at least, that's news to me and the regulation does not mention it.
(1)(i) Subject to paragraph (c)(1)(ii) of this section, a person's purchase or sale is not "on the basis of" material nonpublic information if the person making the purchase or sale demonstrates that:
(A) before becoming aware of the information, the person had:
(1) entered into a binding contract to purchase or sell the security,
(2) instructed another person to purchase or sell the security for the instructing person's account, or
(3) adopted a written plan for trading securities;
(B) the contract, instruction, or plan described in paragraph (c)(1)(i)(A) of this Section:
(1) specified the amount of securities to be purchased or sold and the price at which and the date on which the securities were to be purchased or sold;
(2) included a written formula or algorithm, or computer program, for determining the amount of securities to be purchased or sold and the price at which and the date on which the securities were to be purchased or sold; or
(3) did not permit the person to exercise any subsequent influence over how, when, or whether to effect purchases or sales; provided, in addition, that any other person who, pursuant to the contract, instruction, or plan, did exercise such influence must not have been aware of the material nonpublic information when doing so; and
(C) the purchase or sale that occurred was pursuant to the contract, instruction, or plan. A purchase or sale is not "pursuant to a contract, instruction, or plan" if, among other things, the person who entered into the contract, instruction, or plan altered or deviated from the contract, instruction, or plan to purchase or sell securities (whether by changing the amount, price, or timing of the purchase or sale), or entered into or altered a corresponding or hedging transaction or position with respect to those securities.
Moreover, it is Ruth Kunath's form indicates her sales were pursuant to a 10b-5 plan, and while I could be wrong, I think she sold everything at once.
However, as RKrules points out, the same attorney signed for Kunath and Gold, and he disclosed the plan on her form but not Gold's. It is extremely unlikely an he would vary his practice for two members of management of the same country. And it is highly unlikely Monique would have failed to mention this fact in the two interviews she gave. So I agree, it did not happen here.