JLPT2 G5 S8 F583
The relevant seal inscription form of ?# shows the palm of an open hand (symbolizing a handprint as a guarantee) + 廾 pair of hands (suggesting the parties involved in a transaction) → wooden slat on which handprints were made as a guarantee. As proof of a transaction, this slat was cut in two, each piece wrapped/rolled up with an encircling cord, and one piece given to each of the two parties involved. 券 adds 刀 sword/knife (for emphasis/clarification) → cut slats serving as proof of a transaction into two pieces → *draft*; *certificate*; *ticket*.
[Full Kanji Etymology List]