Is it teams' or team's?

Answer:
Depends.

If its one team owning something:

"The win depends on the team's quarterback."


If its more than one team owning something:

"This will be the highest scoring game in both teams' histories"
First answer by Stiqman. Last edit by Stiqman. Contributor trust: 0 [recommend contributor recommended]. Question popularity: 24 [recommend question].