Below are two situational charts of Examples 8 and 9 of Treas. Reg. §1.1361-5(b)(3). The first chart is Example 8, where the merger of an S corporation into its Qsub (with the subsidiary surviving) was treated as an “F” reorganization. Although the Qsub election for the subsidiary terminates, under Rev. Rul. 64-250 the “S” election does not terminate upon an “F” reorganization.
The second chart is Example 9, where the sale of a Qsub by an S corporation is treated as a sale of assets by the S corporation and is treated as a purchase of assets by the acquiring corporation, followed by a deemed contribution of the assets into a newly formed corporation.
The charts can be viewed as PDF files here: 1.1361-5(b)(3), Example 8 and 1.1361-5(b)(3), Example 9.