Here’s a Pentominous Borders, a type that will be on the US GP round next weekend.
Rules Split the grid into pentominos by placing some walls between cells. Pentominos that touch by an edge must be different, where two pentominos are considered the same if one can be rotated and/or reflected to become the other. Some walls are already given. Black cells aren’t part of the grid.
Or see the instruction booklet.