Puzzlerium tour: Pentomino Areas

Pentomino Areas is an adaptation of the "Penta" puzzle, where outside clues are discarded and the grid is subdivided into regions to enforce new constraints on the pentomino shapes. Although I was not the first to write a Pentomino Areas puzzle, I certainly did bring it to the fore, inspiring several other Pentomino Areas works that followed. 

This enchanting genre opens up avenues for applying solving strategies generally not available to Penta. Quickly listing them down, one can most often do with three methods:

1. Identifying triples/quadruples that are the only possible shapes some of the regions can accommodate, leading to elimination through exhaustion (this is a dynamic list changing as you fill the regions) 

2. Marking cells that cannot be used by any shape.

3. Identifying the regions where a certain constrained shape can fit in.

Rules:  Place the full set of pentominoes into a 12x12 grid, one per bold outlined

region, with rotations and reflections allowed. Pentominoes cannot touch each other, not even diagonally. Also, each pentomino must be fully contained in its

containing region.